CVE-2026-77519 MaxKB: Expired application API keys remain usable on `/chat/api/mcp`
Attackers can use expired API keys to access MCP endpoints, read tool metadata, and modify chat records in MaxKB.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-77519?
CVE-2026-77519 is a medium-severity authentication bypass vulnerability in 1Panel-dev MaxKB, published on 21 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
MaxKB is an open-source AI assistant for enterprise. In 2.10.2-lts and earlier, the /chat/api/mcp authentication path looks up an ApplicationApiKey using only its secret and active status, without enforcing the is_permanent and expire_time checks used by the standard chat API. A previously valid, non-permanent application key that remains active after expiration can initialize the MCP endpoint, list the published application's tool metadata, invoke tools/call, and create durable application_chat and application_chat_record state even though /chat/api/open rejects the same key. No fixed version is available as of this review.
Weakness: CWE-613
Which versions are affected by CVE-2026-77519?
How do I fix CVE-2026-77519?
No fix has been published for CVE-2026-77519 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-77519 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-77519 exists.
Sources
Also known as GHSA-r6g6-69fh-c39q.