CVE-2026-6542 Monitor API allows cross-user read of transaction logs and deletion of build data via flow_id
Attackers can read other users' transaction logs and delete their build data by manipulating flow_id parameters in IBM 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-2026-6542?
CVE-2026-6542 is a medium-severity missing authorization vulnerability in Langflow Langflow, published on 30 Apr 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 1.8.4 could allow any user to supply a flow_id to read transaction logs and vertex build data belonging to other users, and to delete persisted vertex build data for another user's flow.
Weakness: CWE-639
Which versions are affected by CVE-2026-6542?
It affects 1 product.
Products include Langflow Langflow.
How do I fix CVE-2026-6542?
No fix has been published for CVE-2026-6542 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-2026-6542 being exploited?
There is no known exploitation of CVE-2026-6542 in the wild and no public exploit code.
Other vulnerabilities in Langflow Langflow
Sources
Also known as GHSA-fh42-wc28-9xg3.