CVE-2026-56104

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.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
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://www.vulncheck.com/advisories/chainlit-session-hijacking-via-websocket-session-restoration

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-22 16:16

Updated : 2026-07-14 22:17

NVD link : CVE-2026-56104

Mitre link : CVE-2026-56104

CVE.ORG link : CVE-2026-56104

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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