diff --git a/backend/src/ee/routes/v1/ldap-router.ts b/backend/src/ee/routes/v1/ldap-router.ts
index 48674abf37..7047039ff0 100644
--- a/backend/src/ee/routes/v1/ldap-router.ts
+++ b/backend/src/ee/routes/v1/ldap-router.ts
@@ -74,8 +74,8 @@ export const registerLdapRouter = async (server: FastifyZodProvider) => {
                 ldapConfigId: ldapConfig.id,
                 externalId: user.uidNumber,
                 username: user.uid,
-                firstName: user.givenName,
-                lastName: user.sn,
+                firstName: user.givenName ?? user.cn ?? "",
+                lastName: user.sn ?? "",
                 emails: user.mail ? [user.mail] : [],
                 relayState: ((req as unknown as FastifyRequest).body as { RelayState?: string }).RelayState,
                 orgId: (req as unknown as FastifyRequest).ldapConfig.organization
@@ -115,8 +115,8 @@ export const registerLdapRouter = async (server: FastifyZodProvider) => {
                 ldapConfigId: ldapConfig.id,
                 externalId: user.uidNumber,
                 username: user.uid,
-                firstName: user.givenName,
-                lastName: user.sn,
+                firstName: user.givenName ?? user.cn ?? "",
+                lastName: user.sn ?? "",
                 emails: user.mail ? [user.mail] : [],
                 groups,
                 relayState: ((req as unknown as FastifyRequest).body as { RelayState?: string }).RelayState,