[client] Resolve profiles for the sudo invoking user instead of root (#7238)

* [client] Resolve profiles for the sudo invoking user instead of root The SSH server flags force `netbird up` through sudo, but the CLI resolved every per-user path with the process user. As root that reads root's own (empty) local state, so a `sudo netbird up` silently switched the daemon from the user's profile to the default one — cancelling any login already waiting in the browser — and then ran an SSO login for the default profile's config. Whichever account that login returned, the default profile's peer belongs to someone else, so every attempt ended in "peer is already registered by a different User or a Setup Key", with nothing telling the user why. Resolve the acting user through SUDO_USER when running as root: the active profile, the profile config paths and the stored account email now come from the invoking user's directories. Privilege decisions are untouched — they stay on the kernel credentials of the daemon connection, which an environment variable can never influence; a forged SUDO_USER only selects a profile root could select anyway. The invoking user's directories are strictly read-only under sudo. Anything root wrote there would be root-owned and break the user's own runs, so instead of chowning files back, the local writes are skipped: the active-profile bookkeeping and the account-email state simply do not update from a sudo run (the daemon records the switch on its side; a skipped email write costs at most one extra account prompt later). Plain root — no sudo context — has no user to act for, so the ambiguity is refused instead of guessed at: when the daemon's active profile differs from what root resolves and no --profile was given, up fails with a message naming both profiles, instead of silently switching the daemon and failing later with the ownership error. * [client] Act on the daemon-resolved profile and fail closed in the root guard Under sudo the local active-profile mirror is not updated, so up/login re-reading it after a profile switch acted on the previous profile; use the daemon-resolved ID directly instead. The plain-root guard now runs after the readiness wait, denies on lookup errors and empty responses, and matches the owning username as well; an unowned profile (fresh install) and a daemon predating the RPC stay allowed. Write-skip decisions key off the sudo environment alone so a transient user lookup failure cannot turn a run into writing root-owned files into the user's directory, and RemoveProfileState honors the read-only rule too. * [client] Return a wrapped error instead of double-reporting the dial failure * [client] Read the profile from the daemon when the local mirror is not authoritative Under sudo without --profile, `up` took the active profile from the invoking user's local active_profile.txt mirror and drove the daemon to it. But that mirror is never written under sudo (the SwitchProfile write is a no-op), so it goes stale after any --profile run and silently switches the daemon back to the mirror's default. The plain-root guard was meant to refuse exactly this ambiguity but only ran for plain root, never for the sudo case the fix targets. When there is no --profile and the mirror is not authoritative (sudo or plain root), take the profile the daemon already holds for the invoking user instead of the stale mirror: stay on the user's current profile when the daemon owns it (or it is unowned, as on a fresh install), and refuse with a --profile hint when the daemon is on another user's profile. A daemon predating the RPC keeps the mirror-derived profile. Reproduce (before this change): 1. As a non-root user misha, with the daemon installed and running: sudo netbird up --profile work misha connects on the `work` profile. 2. Because the local mirror write is skipped under sudo, ~misha/.config/netbird/active_profile.txt still says `default` (or is still absent, which also resolves to `default`). 3. Run a bare: sudo netbird up The CLI reads `default` from the frozen mirror and sends ProfileName=default; the daemon silently switches away from `work` and brings the tunnel up on `default` — a different account/peer than the one last chosen, with no warning. After this change step 3 stays on `work`. * [client] Return a sentinel error instead of nil-nil for the missing daemon RPC * [client] Load the extend-session hint from the resolved profile * [client] Fail closed instead of reading root's config when the sudo user lookup fails * [client] Fail closed in InvokingUser when the sudo user lookup fails A previous change made baseConfigDir fail closed when SUDO_USER cannot be resolved, but InvokingUser still fell through to user.Current(). Those two guards disagreed: the active-profile mirror and the email state refused to read root's directory, while every profile-path caller happily resolved as root. The consequence of a transient NSS failure under sudo was that Profile.FilePath resolved through getConfigDirForUser("root"), creating /var/lib/netbird/root and reading the profile JSON from there, and the CLI sent Username "root" to the daemon in SetConfig and ListProfiles, so the daemon resolved the same phantom namespace. The invoking user was silently moved onto a root-owned profile instead of being told the lookup failed. Fail closed at the single source of the fallback. getConfigDirForUser is left alone on purpose: it is a pure path helper that also serves daemon-supplied usernames, and under sudo with a successful lookup it must still create the invoking user's own profile directory.
2026-09-01 20:41:28 +02:00 · 2026-09-01 12:50:03 +02:00
parent 352a1d348a
commit 4749005a50
11 changed files with 557 additions and 47 deletions
--- a/client/cmd/debug.go
+++ b/client/cmd/debug.go
@@ -3,7 +3,6 @@ package cmd
 import (
 	"context"
 	"fmt"
-	"os/user"
 	"strings"
 	"time"

@@ -114,7 +113,7 @@ func debugConfigDump(cmd *cobra.Command, _ []string) error {
 	if err != nil {
 		return fmt.Errorf("get active profile: %v", err)
 	}
-	currUser, err := user.Current()
+	currUser, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %v", err)
 	}
--- a/client/cmd/login.go
+++ b/client/cmd/login.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"os"
-	"os/user"
 	"strings"

 	log "github.com/sirupsen/logrus"
@@ -53,7 +52,7 @@ var loginCmd = &cobra.Command{
 			// nolint
 			ctx = context.WithValue(ctx, system.DeviceNameCtxKey, hostName)
 		}
-		username, err := user.Current()
+		username, err := profilemanager.InvokingUser()
 		if err != nil {
 			return fmt.Errorf("get current user: %v", err)
 		}
@@ -74,7 +73,7 @@ var loginCmd = &cobra.Command{
 			if providedSetupKey != "" {
 				return fmt.Errorf("--extend cannot be combined with a setup key; setup keys can only enrol new peers")
 			}
-			if err := doExtendSession(ctx, cmd); err != nil {
+			if err := doExtendSession(ctx, cmd, activeProf); err != nil {
 				return fmt.Errorf("extend session failed: %v", err)
 			}
 			return nil
@@ -176,7 +175,7 @@ func doDaemonLogin(ctx context.Context, cmd *cobra.Command, providedSetupKey str
 // (browser + verification URL) and the resulting JWT is forwarded to the
 // management server's ExtendAuthSession RPC. The tunnel stays up
 // throughout — no Down/Up, no network-map resync.
-func doExtendSession(ctx context.Context, cmd *cobra.Command) error {
+func doExtendSession(ctx context.Context, cmd *cobra.Command, activeProf *profilemanager.Profile) error {
 	conn, err := DialClientGRPCServer(ctx, daemonAddr)
 	if err != nil {
 		//nolint
@@ -190,14 +189,12 @@ func doExtendSession(ctx context.Context, cmd *cobra.Command) error {

 	// the CLI runs in the user's session, the daemon does not: tell it what we can see
 	req := &proto.RequestExtendAuthSessionRequest{HasGraphicalSession: util.HasGraphicalSession()}
-	// Pre-fill the IdP login hint from the active profile so the user
+	// Pre-fill the IdP login hint from the resolved profile so the user
 	// doesn't have to retype their email. Best-effort: we still proceed
 	// without a hint if the lookup fails.
 	pm := profilemanager.NewProfileManager()
-	if active, perr := pm.GetActiveProfile(); perr == nil {
-		if profState, sperr := pm.GetProfileState(active.ID); sperr == nil && profState.Email != "" {
-			req.Hint = &profState.Email
-		}
+	if profState, perr := pm.GetProfileState(activeProf.ID); perr == nil && profState.Email != "" {
+		req.Hint = &profState.Email
 	}

 	startResp, err := client.RequestExtendAuthSession(ctx, req)
@@ -235,9 +232,11 @@ func getActiveProfile(ctx context.Context, pm *profilemanager.ProfileManager, pr
 	// switch profile if provided

 	if profileName != "" {
-		if err := switchProfileOnDaemon(ctx, pm, profileName, username); err != nil {
+		prof, err := switchProfileOnDaemon(ctx, pm, profileName, username)
+		if err != nil {
 			return nil, fmt.Errorf("switch profile: %v", err)
 		}
+		return prof, nil
 	}

 	activeProf, err := pm.GetActiveProfile()
@@ -251,20 +250,19 @@ func getActiveProfile(ctx context.Context, pm *profilemanager.ProfileManager, pr
 	return activeProf, nil
 }

-func switchProfileOnDaemon(ctx context.Context, pm *profilemanager.ProfileManager, handle string, username string) error {
+func switchProfileOnDaemon(ctx context.Context, pm *profilemanager.ProfileManager, handle string, username string) (*profilemanager.Profile, error) {
 	resolvedID, err := switchProfile(ctx, handle, username)
 	if err != nil {
-		return fmt.Errorf("switch profile on daemon: %v", err)
+		return nil, fmt.Errorf("switch profile on daemon: %v", err)
 	}

 	if err := pm.SwitchProfile(resolvedID); err != nil {
-		return fmt.Errorf("switch profile: %v", err)
+		return nil, fmt.Errorf("switch profile: %v", err)
 	}

 	conn, err := DialClientGRPCServer(ctx, daemonAddr)
 	if err != nil {
-		log.Errorf("failed to connect to service CLI interface %v", err)
-		return err
+		return nil, fmt.Errorf("connect to service CLI interface: %w", err)
 	}
 	defer conn.Close()

@@ -272,17 +270,17 @@ func switchProfileOnDaemon(ctx context.Context, pm *profilemanager.ProfileManage

 	status, err := client.Status(ctx, &proto.StatusRequest{})
 	if err != nil {
-		return fmt.Errorf("unable to get daemon status: %v", err)
+		return nil, fmt.Errorf("unable to get daemon status: %v", err)
 	}

 	if status.Status == string(internal.StatusConnected) {
 		if _, err := client.Down(ctx, &proto.DownRequest{}); err != nil {
 			log.Errorf("call service down method: %v", err)
-			return err
+			return nil, err
 		}
 	}

-	return nil
+	return &profilemanager.Profile{ID: resolvedID}, nil
 }

 // switchProfile asks the daemon to switch to the profile identified by
--- a/client/cmd/logout.go
+++ b/client/cmd/logout.go
@@ -3,11 +3,11 @@ package cmd
 import (
 	"context"
 	"fmt"
-	"os/user"
 	"time"

 	"github.com/spf13/cobra"

+	"github.com/netbirdio/netbird/client/internal/profilemanager"
 	"github.com/netbirdio/netbird/client/proto"
 )

@@ -37,7 +37,7 @@ var logoutCmd = &cobra.Command{
 		if profileName != "" {
 			req.ProfileName = &profileName

-			currUser, err := user.Current()
+			currUser, err := profilemanager.InvokingUser()
 			if err != nil {
 				return fmt.Errorf("get current user: %v", err)
 			}
--- a/client/cmd/profile.go
+++ b/client/cmd/profile.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"os/user"
 	"strings"
 	"text/tabwriter"
 	"time"
@@ -97,7 +96,7 @@ func listProfilesFunc(cmd *cobra.Command, _ []string) error {
 	}
 	defer conn.Close()

-	currUser, err := user.Current()
+	currUser, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %w", err)
 	}
@@ -138,7 +137,7 @@ func addProfileFunc(cmd *cobra.Command, args []string) error {
 		return err
 	}

-	currUser, err := user.Current()
+	currUser, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %w", err)
 	}
@@ -179,7 +178,7 @@ func renameProfileFunc(cmd *cobra.Command, args []string) error {
 	}
 	defer conn.Close()

-	currUser, err := user.Current()
+	currUser, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %w", err)
 	}
@@ -233,7 +232,7 @@ func removeProfileFunc(cmd *cobra.Command, args []string) error {
 	}
 	defer conn.Close()

-	currUser, err := user.Current()
+	currUser, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %w", err)
 	}
@@ -261,7 +260,7 @@ func selectProfileFunc(cmd *cobra.Command, args []string) error {
 	profileManager := profilemanager.NewProfileManager()
 	handle := args[0]

-	currUser, err := user.Current()
+	currUser, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %w", err)
 	}
--- a/client/cmd/up.go
+++ b/client/cmd/up.go
@@ -2,10 +2,10 @@ package cmd

 import (
 	"context"
+	"errors"
 	"fmt"
 	"net"
 	"net/netip"
-	"os/user"
 	"runtime"
 	"strings"
 	"time"
@@ -48,6 +48,8 @@ const (
 	profileNameDesc = "profile name to use for the login. If not specified, the last used profile will be used."
 )

+var errDaemonActiveProfileUnsupported = errors.New("daemon does not support active profile lookup")
+
 var (
 	foregroundMode     bool
 	dnsLabels          []string
@@ -122,23 +124,25 @@ func upFunc(cmd *cobra.Command, args []string) error {

 	pm := profilemanager.NewProfileManager()

-	username, err := user.Current()
+	username, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %v", err)
 	}

+	var activeProf *profilemanager.Profile
 	var profileSwitched bool
 	// switch profile if provided
 	if profileName != "" {
-		if err := switchOrCreateProfile(cmd.Context(), pm, profileName, username.Username); err != nil {
+		activeProf, err = switchOrCreateProfile(cmd.Context(), pm, profileName, username.Username)
+		if err != nil {
 			return fmt.Errorf("switch profile: %v", err)
 		}
 		profileSwitched = true
-	}
-
-	activeProf, err := pm.GetActiveProfile()
-	if err != nil {
-		return fmt.Errorf("get active profile: %v", err)
+	} else {
+		activeProf, err = pm.GetActiveProfile()
+		if err != nil {
+			return fmt.Errorf("get active profile: %v", err)
+		}
 	}

 	if foregroundMode {
@@ -150,13 +154,15 @@ func upFunc(cmd *cobra.Command, args []string) error {
 // switchOrCreateProfile switches the active profile to the one identified by
 // handle, creating it first when it does not exist yet. This restores the
 // pre-0.73 behaviour where `netbird up --profile <name>` auto-creates a
-// missing profile instead of failing.
-func switchOrCreateProfile(ctx context.Context, pm *profilemanager.ProfileManager, handle, username string) error {
+// missing profile instead of failing. Returns the daemon-resolved profile so
+// callers act on it directly instead of re-reading the local state, which is
+// not updated under sudo.
+func switchOrCreateProfile(ctx context.Context, pm *profilemanager.ProfileManager, handle, username string) (*profilemanager.Profile, error) {
 	resolvedID, err := switchProfile(ctx, handle, username)
 	if err != nil {
 		st, ok := gstatus.FromError(err)
 		if !ok || st.Code() != codes.NotFound {
-			return err
+			return nil, err
 		}
 		// Don't fail immediately on a create error: a concurrent run may
 		// have created the profile between the NotFound above and this
@@ -165,16 +171,16 @@ func switchOrCreateProfile(ctx context.Context, pm *profilemanager.ProfileManage
 		_, createErr := createProfile(ctx, handle, username)
 		if resolvedID, err = switchProfile(ctx, handle, username); err != nil {
 			if createErr != nil {
-				return fmt.Errorf("create profile: %w", createErr)
+				return nil, fmt.Errorf("create profile: %w", createErr)
 			}
-			return err
+			return nil, err
 		}
 	}

 	if err := pm.SwitchProfile(resolvedID); err != nil {
-		return err
+		return nil, err
 	}
-	return nil
+	return &profilemanager.Profile{ID: resolvedID}, nil
 }

 // createProfile dials the daemon and creates a new profile with the given
@@ -302,6 +308,30 @@ func runInDaemonMode(ctx context.Context, cmd *cobra.Command, pm *profilemanager
 		return fmt.Errorf("unable to get daemon status: %v", err)
 	}

+	// Under sudo the invoking user's local active-profile mirror is never
+	// written (the SwitchProfile write is a no-op), and plain root has no
+	// invoking user at all — so the mirror read into activeProf above is stale
+	// or defaulted and must not drive the daemon. With no --profile to make the
+	// choice explicit, take the profile the daemon already holds for this user
+	// instead: it stays on the user's current profile rather than silently
+	// switching to the mirror's default, and refuses when the daemon is on
+	// another user's profile.
+	if profileName == "" && !profilemanager.MirrorIsAuthoritative() {
+		u, err := profilemanager.InvokingUser()
+		if err != nil {
+			return fmt.Errorf("get current user: %v", err)
+		}
+		resolved, err := daemonActiveProfileForUser(ctx, client, u.Username)
+		switch {
+		case errors.Is(err, errDaemonActiveProfileUnsupported):
+			log.Warnf("keeping the locally resolved profile: %v", err)
+		case err != nil:
+			return err
+		default:
+			activeProf = resolved
+		}
+	}
+
 	if status.Status == string(internal.StatusConnected) {
 		if !profileSwitched {
 			cmd.Println("Already connected")
@@ -314,7 +344,7 @@ func runInDaemonMode(ctx context.Context, cmd *cobra.Command, pm *profilemanager
 		}
 	}

-	username, err := user.Current()
+	username, err := profilemanager.InvokingUser()
 	if err != nil {
 		return fmt.Errorf("get current user: %v", err)
 	}
@@ -881,3 +911,31 @@ func isValidAddrPort(input string) bool {
 	_, err := netip.ParseAddrPort(input)
 	return err == nil
 }
+
+// daemonActiveProfileForUser returns the profile the daemon currently holds for
+// username, for the no --profile case where the local mirror is not
+// authoritative (sudo or plain root). It returns that profile when the daemon
+// owns it for this user or when the profile is unowned (empty username, as on a
+// fresh install), so the caller acts on the daemon's real state instead of the
+// stale mirror. It denies with a --profile hint when the daemon is on another
+// user's profile, when the lookup fails, or when the daemon reports no active
+// profile. Returns errDaemonActiveProfileUnsupported when the daemon predates
+// the RPC; the caller keeps the mirror-derived profile in that case.
+func daemonActiveProfileForUser(ctx context.Context, client proto.DaemonServiceClient, username string) (*profilemanager.Profile, error) {
+	active, err := client.GetActiveProfile(ctx, &proto.GetActiveProfileRequest{})
+	if err != nil {
+		if st, ok := gstatus.FromError(err); ok && st.Code() == codes.Unimplemented {
+			return nil, fmt.Errorf("%w: %v", errDaemonActiveProfileUnsupported, err)
+		}
+		return nil, fmt.Errorf("pass --profile to choose the profile explicitly: the daemon's active profile could not be verified: %v", err)
+	}
+	if active.GetId() == "" {
+		return nil, fmt.Errorf("pass --profile to choose the profile explicitly: the daemon reported no active profile")
+	}
+	if active.GetUsername() != "" && active.GetUsername() != username {
+		return nil, fmt.Errorf(
+			"pass --profile to choose the profile explicitly: the daemon's active profile is %q (user %q) but this invocation runs for %q",
+			active.GetProfileName(), active.GetUsername(), username)
+	}
+	return &profilemanager.Profile{ID: profilemanager.ID(active.GetId())}, nil
+}
--- a/client/cmd/up_test.go
+++ b/client/cmd/up_test.go
@@ -0,0 +1,88 @@
+package cmd
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	gstatus "google.golang.org/grpc/status"
+
+	"github.com/netbirdio/netbird/client/internal/profilemanager"
+	"github.com/netbirdio/netbird/client/proto"
+)
+
+type fakeActiveProfileClient struct {
+	proto.DaemonServiceClient
+	resp *proto.GetActiveProfileResponse
+	err  error
+}
+
+func (f *fakeActiveProfileClient) GetActiveProfile(_ context.Context, _ *proto.GetActiveProfileRequest, _ ...grpc.CallOption) (*proto.GetActiveProfileResponse, error) {
+	return f.resp, f.err
+}
+
+func TestDaemonActiveProfileForUserReturnsOwnProfile(t *testing.T) {
+	client := &fakeActiveProfileClient{resp: &proto.GetActiveProfileResponse{Id: "default", ProfileName: "default", Username: "root"}}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.NoError(t, err)
+	require.NotNil(t, prof)
+	assert.Equal(t, profilemanager.ID("default"), prof.ID)
+}
+
+func TestDaemonActiveProfileForUserReturnsUnownedProfile(t *testing.T) {
+	client := &fakeActiveProfileClient{resp: &proto.GetActiveProfileResponse{Id: "default", ProfileName: "default", Username: ""}}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.NoError(t, err)
+	require.NotNil(t, prof)
+	assert.Equal(t, profilemanager.ID("default"), prof.ID)
+}
+
+func TestDaemonActiveProfileForUserKeepsDaemonProfileOverStaleMirror(t *testing.T) {
+	client := &fakeActiveProfileClient{resp: &proto.GetActiveProfileResponse{Id: "ab12", ProfileName: "work", Username: "misha"}}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "misha")
+	require.NoError(t, err)
+	require.NotNil(t, prof)
+	assert.Equal(t, profilemanager.ID("ab12"), prof.ID)
+}
+
+func TestDaemonActiveProfileForUserRejectsOtherUsersProfile(t *testing.T) {
+	client := &fakeActiveProfileClient{resp: &proto.GetActiveProfileResponse{Id: "ab12", ProfileName: "work", Username: "misha"}}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.Error(t, err)
+	assert.Nil(t, prof)
+	assert.Contains(t, err.Error(), "--profile")
+}
+
+func TestDaemonActiveProfileForUserRejectsOtherUsersDefaultProfile(t *testing.T) {
+	client := &fakeActiveProfileClient{resp: &proto.GetActiveProfileResponse{Id: "default", ProfileName: "default", Username: "misha"}}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.Error(t, err)
+	assert.Nil(t, prof)
+	assert.Contains(t, err.Error(), "--profile")
+}
+
+func TestDaemonActiveProfileForUserRejectsLookupError(t *testing.T) {
+	client := &fakeActiveProfileClient{err: gstatus.Error(codes.Internal, "boom")}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.Error(t, err)
+	assert.Nil(t, prof)
+	assert.Contains(t, err.Error(), "--profile")
+}
+
+func TestDaemonActiveProfileForUserRejectsEmptyResponse(t *testing.T) {
+	client := &fakeActiveProfileClient{resp: &proto.GetActiveProfileResponse{}}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.Error(t, err)
+	assert.Nil(t, prof)
+	assert.Contains(t, err.Error(), "--profile")
+}
+
+func TestDaemonActiveProfileForUserKeepsMirrorWhenDaemonWithoutRPC(t *testing.T) {
+	client := &fakeActiveProfileClient{err: gstatus.Error(codes.Unimplemented, "unknown method")}
+	prof, err := daemonActiveProfileForUser(context.Background(), client, "root")
+	require.ErrorIs(t, err, errDaemonActiveProfileUnsupported)
+	assert.Nil(t, prof)
+}
--- a/client/internal/profilemanager/config.go
+++ b/client/internal/profilemanager/config.go
@@ -225,6 +225,12 @@ func getConfigDir() (string, error) {
 	}

 	configDir := filepath.Join(base, "netbird")
+	// Under sudo this is the invoking user's directory and strictly read-only:
+	// anything root creates in it would be root-owned and break the user's own
+	// runs. Reads of a missing directory fall through to defaults.
+	if sudoActive() {
+		return configDir, nil
+	}
 	if err := os.MkdirAll(configDir, 0o755); err != nil {
 		return "", err
 	}
@@ -232,6 +238,16 @@ func getConfigDir() (string, error) {
 }

 func baseConfigDir() (string, error) {
+	if u, ok := sudoInvokingUser(); ok {
+		return userBaseConfigDir(u)
+	}
+	// Fail closed instead of falling through to root's own config directory:
+	// reading root's active-profile and email state for what is actually the
+	// invoking user's invocation is the very confusion this resolution exists
+	// to prevent.
+	if sudoActive() {
+		return "", fmt.Errorf("resolve sudo invoking user %q: refusing to fall back to root's config directory", os.Getenv(envSudoUser))
+	}
 	if runtime.GOOS == "darwin" {
 		if u, err := user.Current(); err == nil && u.HomeDir != "" {
 			return filepath.Join(u.HomeDir, "Library", "Application Support"), nil
--- a/client/internal/profilemanager/invoking_user.go
+++ b/client/internal/profilemanager/invoking_user.go
@@ -0,0 +1,100 @@
+package profilemanager
+
+import (
+	"fmt"
+	"os"
+	"os/user"
+	"path/filepath"
+	"runtime"
+
+	log "github.com/sirupsen/logrus"
+)
+
+const envSudoUser = "SUDO_USER"
+
+var (
+	geteuid    = os.Geteuid
+	lookupUser = user.Lookup
+)
+
+// InvokingUser returns the user a CLI invocation acts for. Under sudo that is
+// the user who ran sudo, not root: privileged flags force commands through
+// sudo, and resolving profiles as root would silently switch the daemon to
+// root's (default) profile instead of the invoking user's. Privilege decisions
+// are not made here — those stay on the kernel credentials of the daemon
+// connection, which SUDO_USER (a plain environment variable) can never
+// influence; a forged value only selects a profile root could select anyway.
+func InvokingUser() (*user.User, error) {
+	if u, ok := sudoInvokingUser(); ok {
+		return u, nil
+	}
+	// Fail closed instead of falling through to root: every caller feeds this
+	// username into profile-path resolution, so a lookup failure would resolve
+	// (and create) a root-owned profile namespace and switch the daemon onto it
+	// behind the invoking user's back.
+	if sudoActive() {
+		return nil, fmt.Errorf("resolve sudo invoking user %q: refusing to fall back to root", os.Getenv(envSudoUser))
+	}
+	return user.Current()
+}
+
+// IsPlainRoot reports that the process runs as root with no usable sudo
+// context: there is no invoking user to act for, so per-user resolution falls
+// back to root's own (empty) state. Callers use it to refuse ambiguous
+// operations instead of silently acting on the wrong profile.
+func IsPlainRoot() bool {
+	if geteuid() != 0 {
+		return false
+	}
+	_, ok := sudoInvokingUser()
+	return !ok
+}
+
+// MirrorIsAuthoritative reports whether the invoking user's local
+// active-profile mirror can be trusted as the profile selector. It cannot under
+// sudo (writes to it are skipped, so it goes stale) or as plain root (there is
+// no invoking user, so it falls back to root's own default). Callers use it to
+// decide whether to read the profile from the mirror or from the daemon.
+func MirrorIsAuthoritative() bool {
+	return !sudoActive() && !IsPlainRoot()
+}
+
+// sudoInvokingUser resolves SUDO_USER when the process runs as root under
+// sudo. Returns false whenever the sudo context is absent or unusable, in
+// which case callers fall back to the process user.
+func sudoInvokingUser() (*user.User, bool) {
+	if !sudoActive() {
+		return nil, false
+	}
+	name := os.Getenv(envSudoUser)
+	u, err := lookupUser(name)
+	if err != nil {
+		log.Warnf("sudo invoking user %q lookup: %v", name, err)
+		return nil, false
+	}
+	return u, true
+}
+
+// sudoActive reports a sudo context from the environment alone: write-skip
+// decisions key off it so a transient user lookup failure can never flip a
+// run from read-only to writing root-owned files into the user's directory.
+func sudoActive() bool {
+	if geteuid() != 0 {
+		return false
+	}
+	name := os.Getenv(envSudoUser)
+	return name != "" && name != "root"
+}
+
+// userBaseConfigDir mirrors os.UserConfigDir for a user other than the process
+// owner. Environment overrides (XDG_CONFIG_HOME) cannot be honoured here: under
+// sudo the environment is root's, not the invoking user's.
+func userBaseConfigDir(u *user.User) (string, error) {
+	if u.HomeDir == "" {
+		return "", fmt.Errorf("user %s has no home directory", u.Username)
+	}
+	if runtime.GOOS == "darwin" {
+		return filepath.Join(u.HomeDir, "Library", "Application Support"), nil
+	}
+	return filepath.Join(u.HomeDir, ".config"), nil
+}
--- a/client/internal/profilemanager/invoking_user_test.go
+++ b/client/internal/profilemanager/invoking_user_test.go
@@ -0,0 +1,230 @@
+package profilemanager
+
+import (
+	"errors"
+	"io/fs"
+	"os"
+	"os/user"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestInvokingUserFallsBackToProcessUser(t *testing.T) {
+	t.Setenv(envSudoUser, "")
+
+	got, err := InvokingUser()
+	require.NoError(t, err)
+
+	current, err := user.Current()
+	require.NoError(t, err)
+	assert.Equal(t, current.Username, got.Username)
+}
+
+func TestSudoInvokingUserInactiveWithoutSudoContext(t *testing.T) {
+	t.Setenv(envSudoUser, "")
+	_, ok := sudoInvokingUser()
+	assert.False(t, ok)
+}
+
+func TestSudoInvokingUserIgnoresRoot(t *testing.T) {
+	t.Setenv(envSudoUser, "root")
+	origEuid := geteuid
+	geteuid = func() int { return 0 }
+	t.Cleanup(func() { geteuid = origEuid })
+
+	_, ok := sudoInvokingUser()
+	assert.False(t, ok, "sudo from a root shell must not redirect anything")
+	assert.False(t, sudoActive())
+	assert.True(t, IsPlainRoot())
+}
+
+func TestSudoInvokingUserResolvesInvokingUser(t *testing.T) {
+	fakeSudo(t, filepath.Join("/home", "misha"))
+
+	u, ok := sudoInvokingUser()
+	require.True(t, ok)
+	assert.Equal(t, "misha", u.Username)
+
+	got, err := InvokingUser()
+	require.NoError(t, err)
+	assert.Equal(t, "misha", got.Username)
+
+	assert.False(t, IsPlainRoot())
+}
+
+func TestInvokingUserFailsClosedWhenSudoLookupFails(t *testing.T) {
+	fakeSudo(t, filepath.Join("/home", "misha"))
+	lookupUser = func(string) (*user.User, error) { return nil, errors.New("nss unavailable") }
+
+	got, err := InvokingUser()
+	require.Error(t, err)
+	assert.Nil(t, got, "must not resolve to the root process user")
+}
+
+func TestProfileFilePathFailsClosedWhenSudoLookupFails(t *testing.T) {
+	profilesRoot := t.TempDir()
+	fakeSudo(t, filepath.Join("/home", "misha"))
+	lookupUser = func(string) (*user.User, error) { return nil, errors.New("nss unavailable") }
+
+	origDir := DefaultConfigPathDir
+	DefaultConfigPathDir = profilesRoot
+	t.Cleanup(func() { DefaultConfigPathDir = origDir })
+
+	p := &Profile{ID: "0123456789abcdef0123456789abcdef"}
+	_, err := p.FilePath()
+	require.Error(t, err)
+	assertNoEntries(t, profilesRoot)
+}
+
+func TestSudoActiveSurvivesLookupFailure(t *testing.T) {
+	fakeSudo(t, filepath.Join("/home", "misha"))
+	lookupUser = func(string) (*user.User, error) { return nil, errors.New("nss unavailable") }
+
+	_, ok := sudoInvokingUser()
+	assert.False(t, ok)
+	assert.True(t, sudoActive())
+	assert.True(t, IsPlainRoot())
+}
+
+func TestGetConfigDirUnderSudoIsReadOnly(t *testing.T) {
+	home := t.TempDir()
+	fakeSudo(t, home)
+
+	base, err := baseConfigDir()
+	require.NoError(t, err)
+	if runtime.GOOS == "darwin" {
+		assert.Equal(t, filepath.Join(home, "Library", "Application Support"), base)
+	} else {
+		assert.Equal(t, filepath.Join(home, ".config"), base)
+	}
+
+	dir, err := getConfigDir()
+	require.NoError(t, err)
+	assert.Equal(t, filepath.Join(base, "netbird"), dir)
+	assert.NoDirExists(t, dir)
+}
+
+func TestBaseConfigDirFailsClosedWhenSudoLookupFails(t *testing.T) {
+	fakeSudo(t, filepath.Join("/home", "misha"))
+	lookupUser = func(string) (*user.User, error) { return nil, errors.New("nss unavailable") }
+
+	_, err := baseConfigDir()
+	require.Error(t, err)
+
+	_, err = getConfigDir()
+	require.Error(t, err)
+}
+
+func TestSwitchProfileSkipsStateWriteUnderSudo(t *testing.T) {
+	home := t.TempDir()
+	fakeSudo(t, home)
+
+	pm := NewProfileManager()
+	require.NoError(t, pm.SwitchProfile(defaultProfileName))
+	assertNoEntries(t, home)
+}
+
+func TestSetProfileStateSkipsWriteUnderSudo(t *testing.T) {
+	home := t.TempDir()
+	fakeSudo(t, home)
+
+	pm := NewProfileManager()
+	require.NoError(t, pm.SetProfileState(defaultProfileName, &ProfileState{Email: "misha@example.com"}))
+	assertNoEntries(t, home)
+}
+
+func TestRemoveProfileStateSkipsRemoveUnderSudo(t *testing.T) {
+	home := t.TempDir()
+	stateDir := filepath.Join(home, ".config", "netbird")
+	if runtime.GOOS == "darwin" {
+		stateDir = filepath.Join(home, "Library", "Application Support", "netbird")
+	}
+	require.NoError(t, os.MkdirAll(stateDir, 0o700))
+	stateFile := filepath.Join(stateDir, "default.state.json")
+	require.NoError(t, os.WriteFile(stateFile, []byte(`{"email":"misha@example.com"}`), 0o600))
+
+	fakeSudo(t, home)
+	pm := NewProfileManager()
+	require.NoError(t, pm.RemoveProfileState("default"))
+	assert.FileExists(t, stateFile)
+}
+
+func TestUserBaseConfigDir(t *testing.T) {
+	u := &user.User{Username: "misha", HomeDir: filepath.Join("/home", "misha")}
+	dir, err := userBaseConfigDir(u)
+	require.NoError(t, err)
+	if runtime.GOOS == "darwin" {
+		assert.Equal(t, filepath.Join(u.HomeDir, "Library", "Application Support"), dir)
+	} else {
+		assert.Equal(t, filepath.Join(u.HomeDir, ".config"), dir)
+	}
+
+	_, err = userBaseConfigDir(&user.User{Username: "nohome"})
+	require.Error(t, err)
+}
+
+func TestIsPlainRoot(t *testing.T) {
+	t.Setenv(envSudoUser, "")
+	origEuid := geteuid
+	t.Cleanup(func() { geteuid = origEuid })
+
+	geteuid = func() int { return 1000 }
+	assert.False(t, IsPlainRoot())
+
+	geteuid = func() int { return 0 }
+	assert.True(t, IsPlainRoot())
+}
+
+func TestMirrorIsAuthoritative(t *testing.T) {
+	t.Setenv(envSudoUser, "")
+	origEuid := geteuid
+	t.Cleanup(func() { geteuid = origEuid })
+
+	geteuid = func() int { return 1000 }
+	assert.True(t, MirrorIsAuthoritative(), "a normal user's own mirror is authoritative")
+
+	geteuid = func() int { return 0 }
+	assert.False(t, MirrorIsAuthoritative(), "plain root has no authoritative mirror")
+}
+
+func TestMirrorIsAuthoritativeFalseUnderSudo(t *testing.T) {
+	fakeSudo(t, filepath.Join("/home", "misha"))
+	assert.False(t, MirrorIsAuthoritative(), "the sudo mirror is frozen, so it is not authoritative")
+}
+
+func fakeSudo(t *testing.T, home string) {
+	t.Helper()
+	t.Setenv(envSudoUser, "misha")
+
+	origEuid := geteuid
+	origLookup := lookupUser
+	origOverride := ConfigDirOverride
+	geteuid = func() int { return 0 }
+	lookupUser = func(name string) (*user.User, error) {
+		return &user.User{Username: name, Uid: "1234", Gid: "1234", HomeDir: home}, nil
+	}
+	ConfigDirOverride = ""
+	t.Cleanup(func() {
+		geteuid = origEuid
+		lookupUser = origLookup
+		ConfigDirOverride = origOverride
+	})
+}
+
+func assertNoEntries(t *testing.T, root string) {
+	t.Helper()
+	err := filepath.WalkDir(root, func(path string, _ fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if path != root {
+			t.Errorf("unexpected entry created under %s: %s", root, path)
+		}
+		return nil
+	})
+	require.NoError(t, err)
+}
--- a/client/internal/profilemanager/profilemanager.go
+++ b/client/internal/profilemanager/profilemanager.go
@@ -3,7 +3,6 @@ package profilemanager
 import (
 	"fmt"
 	"os"
-	"os/user"
 	"path/filepath"
 	"strings"
 	"sync"
@@ -54,7 +53,7 @@ func (p *Profile) FilePath() (string, error) {
 		return "", fmt.Errorf("invalid profile ID: %q", id)
 	}

-	username, err := user.Current()
+	username, err := InvokingUser()
 	if err != nil {
 		return "", fmt.Errorf("failed to get current user: %w", err)
 	}
@@ -130,7 +129,7 @@ func (pm *ProfileManager) getActiveProfileState() ID {
 	if err != nil {
 		if !os.IsNotExist(err) {
 			log.Warnf("failed to read active profile state: %v", err)
-		} else {
+		} else if !sudoActive() {
 			if err := pm.setActiveProfileState(defaultProfileName); err != nil {
 				log.Warnf("failed to set default profile state: %v", err)
 			}
@@ -148,6 +147,13 @@ func (pm *ProfileManager) getActiveProfileState() ID {
 }

 func (pm *ProfileManager) setActiveProfileState(id ID) error {
+	// The invoking user's state is read-only under sudo — a root-owned file in
+	// the user's directory would break their own runs. The daemon still records
+	// the switch on its side; only the user-local bookkeeping is skipped.
+	if sudoActive() {
+		log.Infof("running under sudo: not persisting active profile %q for user %s", id, os.Getenv(envSudoUser))
+		return nil
+	}

 	configDir, err := getConfigDir()
 	if err != nil {
--- a/client/internal/profilemanager/state.go
+++ b/client/internal/profilemanager/state.go
@@ -7,6 +7,8 @@ import (
 	"os"
 	"path/filepath"

+	log "github.com/sirupsen/logrus"
+
 	"github.com/netbirdio/netbird/util"
 )

@@ -63,6 +65,15 @@ func (pm *ProfileManager) SetProfileState(id ID, state *ProfileState) error {
 		return fmt.Errorf("invalid profile ID: %q", id)
 	}

+	// The invoking user's state is read-only under sudo. The file only carries
+	// the account email for the login hint and display, so skipping the write
+	// costs at most one extra account prompt later — a root-owned file in the
+	// user's directory would cost every later update instead.
+	if sudoActive() {
+		log.Debugf("running under sudo: not persisting profile state for user %s", os.Getenv(envSudoUser))
+		return nil
+	}
+
 	stateFile := filepath.Join(configDir, id.String()+".state.json")
 	if err := util.WriteJsonWithRestrictedPermission(context.Background(), stateFile, state); err != nil {
 		return fmt.Errorf("write profile state: %w", err)
@@ -92,6 +103,11 @@ func (pm *ProfileManager) SetActiveProfileState(state *ProfileState) error {
 // equivalent to clearing it; the next SSO login recreates it. A missing file
 // is not an error.
 func (pm *ProfileManager) RemoveProfileState(profileName string) error {
+	if sudoActive() {
+		log.Debugf("running under sudo: not removing profile state for user %s", os.Getenv(envSudoUser))
+		return nil
+	}
+
 	configDir, err := getConfigDir()
 	if err != nil {
 		return fmt.Errorf("get config directory: %w", err)