CVE-2026-56104
Chainlit contains a session hijacking vulnerability
Severity by source
Trivy's own label is CRITICAL. Rated critical by GHSA.
Description
Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the restore_existing_session path to assume a victim's permissions and roles, enabling unauthorized invocation of tools and access to data restricted to the authenticated victim.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| pip::GitHub Security Advisory pip | chainlit | 2.10.1 |
References
- https://github.com/Chainlit/chainlit
- https://github.com/Chainlit/chainlit/commit/5effb664f1e0af4a4f0a42fe63ea979676039a7f
- https://github.com/Chainlit/chainlit/pull/2857
- https://github.com/Chainlit/chainlit/releases/tag/2.10.1
- https://nvd.nist.gov/vuln/detail/CVE-2026-56104
- https://www.vulncheck.com/advisories/chainlit-session-hijacking-via-websocket-session-restoration