CVE-2026-86099highCWE-22

CVE-2026-86099: high-severity vulnerability in chainlit

Chainlit through 2.12.0 Path Traversal via socket.io sessionId

Published

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.8epss 0.6%
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Affected products
Chainlit · chainlit
Related CVEs — chainlit

In the same product, most dangerous first.

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