diff --git a/packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/RealmSyncUtils.kt b/packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/RealmSyncUtils.kt
index b86783b6f0..af5463f9a4 100644
--- a/packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/RealmSyncUtils.kt
+++ b/packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/RealmSyncUtils.kt
@@ -200,6 +200,10 @@ internal fun convertAppError(appError: AppError): Throwable {
                         // Custom JWT
                         // See https://github.com/10gen/baas/blob/master/authprovider/providers/custom/provider.go
                         InvalidCredentialsException(msg)
+                    } else if (msg.contains("unauthorized")) {
+                        // Sanitized error messages
+                        // See https://github.com/10gen/baas/pull/14005/files
+                        InvalidCredentialsException(msg)
                     } else {
                         // It does not look possible to reliably detect Facebook, Google and Apple
                         // invalid tokens: https://github.com/10gen/baas/blob/master/authprovider/providers/oauth2/oauth.go#L139
diff --git a/packages/test-sync/src/commonTest/kotlin/io/realm/kotlin/test/mongodb/common/CredentialsTests.kt b/packages/test-sync/src/commonTest/kotlin/io/realm/kotlin/test/mongodb/common/CredentialsTests.kt
index b666ebb3dc..d76391c980 100644
--- a/packages/test-sync/src/commonTest/kotlin/io/realm/kotlin/test/mongodb/common/CredentialsTests.kt
+++ b/packages/test-sync/src/commonTest/kotlin/io/realm/kotlin/test/mongodb/common/CredentialsTests.kt
@@ -369,7 +369,7 @@ class CredentialsTests {
             payload = mapOf("mail" to TestHelper.randomEmail(), "id" to 0)
         )
 
-        assertFailsWithMessage<AuthException>("Error: Authentication failed.") {
+        assertFailsWithMessage<AuthException>("unauthorized") {
             runBlocking {
                 app.login(credentials)
             }
@@ -383,7 +383,7 @@ class CredentialsTests {
             }
             fail()
         } catch (error: AppException) {
-            assertTrue(error.message!!.contains("authentication via"), error.message)
+            assertTrue(error.message!!.contains("unauthorized"), error.message)
         }
     }
 }