CVE-2026-86099Chainlit through 2.12.0 Path Traversal via socket.io sessionId
Updated under an hour ago ()
Does this affect you?
It affects chainlit. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
Chainlit through 2.12.0 fails to validate the client-supplied socket.io sessionId parameter, allowing unauthenticated attackers to traverse filesystem paths by injecting absolute or relative path sequences. Attackers can craft malicious sessionId values that escape the upload directory and recursively delete arbitrary directories accessible to the service process.
- CVSS
- 8.2 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
- Weakness (CWE)
- CWE-22
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- VulnCheck
- NVD analysis
- Deferred
- Record last updated
- Sep 9, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Chainlit chainlit chainlit:chainlit (from the name) | through 2.12.0 | CNA record |
References
- https://github.com/Chainlit/chainlitproduct
- https://github.com/Chainlit/chainlit/blob/2.12.0/backend/chainlit/session.pytechnical-description
- https://github.com/Chainlit/chainlit/blob/2.12.0/backend/chainlit/socket.pytechnical-description
- https://pypi.org/project/chainlit/product
- https://www.vulncheck.com/advisories/chainlit-through-2.12.0-path-traversal-via-socket-io-sessionidthird-party-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.