CVE-2026-12763 Langflow is vulnerable to authentication bypass and insufficient session expiration
An authenticated attacker can access another user's MCP server context due to improper cache key isolation in Langflow OSS.
- 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-2026-12763?
CVE-2026-12763 is a medium-severity missing authorization vulnerability in IBM Langflow OSS, published on 14 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
IBM Langflow OSS 1.0.0 through 1.11.5 could allow an authenticated attacker to access another user's MCP server context due to improper cache key isolation in the MCP Tools component.
Weakness: CWE-306
Which versions are affected by CVE-2026-12763?
How do I fix CVE-2026-12763?
No fix has been published for CVE-2026-12763 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-12763 being exploited?
There is no known exploitation of CVE-2026-12763 in the wild and no public exploit code.
Sources
Also known as GHSA-vhrg-69rg-gwv4.