diff --git a/uds-auth/lib/index.js b/uds-auth/lib/index.js
index 203c95d9..671793d4 100644
--- a/uds-auth/lib/index.js
+++ b/uds-auth/lib/index.js
@@ -1694,6 +1694,31 @@ async function initServices(ctx, config) {
       sessionBridge: _sessionBridge,
     })
 
+    // Revalidate QR-authenticated sessions against the UDS department profile.
+    // The session store still enforces the independent seven-day absolute limit.
+    const udsSessionCheckTimer = setInterval(async () => {
+      let sessions
+      try {
+        sessions = await _sessionStore.listUdsSessionsForValidation()
+      } catch (err) {
+        ctx.logger?.warn?.('[uds-auth] failed to enumerate UDS sessions for validation:', err?.message || err)
+        return
+      }
+      for (const session of sessions) {
+        try {
+          if (!session.token || !await _authMiddleware.verifyEmpNoAndToken(session.empNo, session.token)) {
+            await _sessionStore.revokeSession(session.sessionId)
+            ctx.logger?.info?.('[uds-auth] UDS session revoked after profile validation failed for %s', session.empNo)
+          }
+        } catch (err) {
+          await _sessionStore.revokeSession(session.sessionId).catch(() => {})
+          ctx.logger?.info?.('[uds-auth] UDS session revoked after profile validation error for %s: %s', session.empNo, err?.message || err)
+        }
+      }
+    }, 6 * 60 * 60 * 1000)
+    udsSessionCheckTimer.unref?.()
+    ctx.effect?.(() => () => clearInterval(udsSessionCheckTimer), 'uds-auth: UDS session validation')
+
     _apiHandlers = createApiHandlers(
       { session: INTERNAL.session },
       _sessionStore,
diff --git a/uds-auth/lib/session/memory-store.js b/uds-auth/lib/session/memory-store.js
index 7eef8693..121505d7 100644
--- a/uds-auth/lib/session/memory-store.js
+++ b/uds-auth/lib/session/memory-store.js
@@ -280,6 +280,20 @@ export class MemoryStore extends SessionStore {
     return this._publicRecord(this._purgeExpired(id))
   }
 
+  async listUdsSessionsForValidation() {
+    const sessions = []
+    for (const [sessionId, record] of this._sessions) {
+      const row = this._purgeExpired(sessionId)
+      if (!row || row.kind !== 'uds') continue
+      sessions.push({
+        sessionId: row.sessionId,
+        empNo: row.empNo,
+        token: typeof row.userData?.token === 'string' ? row.userData.token : '',
+      })
+    }
+    return sessions
+  }
+
   getBySessionIdSync(sessionId) {
     const id = String(sessionId || '').trim()
     if (!id) return null
diff --git a/uds-auth/lib/session/store.js b/uds-auth/lib/session/store.js
index 01255ba5..6fb655ff 100644
--- a/uds-auth/lib/session/store.js
+++ b/uds-auth/lib/session/store.js
@@ -27,6 +27,11 @@ export class SessionStore {
     throw new Error('SessionStore#getBySessionId must be implemented')
   }
 
+  /** Return active UDS sessions and their upstream token for periodic validation. */
+  async listUdsSessionsForValidation() {
+    throw new Error('SessionStore#listUdsSessionsForValidation must be implemented')
+  }
+
   async touch(sessionId, ttlSeconds) {
     throw new Error('SessionStore#touch must be implemented')
   }