diff --git a/lib/auth.ts b/lib/auth.ts
index 3f3a7c30..55eaeb22 100644
--- a/lib/auth.ts
+++ b/lib/auth.ts
@@ -15,6 +15,8 @@ export const auth = betterAuth({
     schema,
   }),
   plugins: [dash(), nextCookies()],
+  // names and avatars come from GitHub at sign-up; don't let users rename themselves (e.g. to impersonate someone)
+  disabledPaths: ["/update-user"],
   socialProviders: {
     github: {
       clientId: process.env.GITHUB_CLIENT_ID!,