Chainlit through 2.12.0 Path Traversal via socket.io sessionId
Published Sep 9, 2026 · Updated Oct 23, 2026
Original summary
Normalized public record · Updated Oct 23, 2026
Chainlit through 2.12.0 Path Traversal via socket.io sessionId
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
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.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- MEDIUM
- Confidence
- 10%
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
- GitHub advisory ↗
- Source repository ↗
- Source repository ↗
- PyPI Package ↗
- VulnCheck Advisory: Chainlit through 2.12.0 Path Traversal via socket.io sessionId ↗
Record history
Published Sep 9, 2026 · Last refreshed Oct 23, 2026