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TI-2026-58900 Aliases CVE-2026-86099GHSA-wf68-h55h-fvxv

Chainlit through 2.12.0 Path Traversal via socket.io sessionId

Priority MEDIUM 45CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00598 48th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Chainlitchainlitup to 2.12.0—No fix listedCNA
  • chainlit VendorChainlit Affected up to 2.12.0 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-86099
  2. 2026-10-03 Alias added: GHSA-wf68-h55h-fvxv

References

Other 4

  • TI-2026-32874 Chainlit: Command injection via MCP stdio transport allows unauthenticated remote code execution CVSS 3.1CRITICAL 9.8
  • TI-2026-17828 Chainlit < 2.9.4 Arbitrary File Read via /project/element CVSS 4.0HIGH 7.1
  • TI-2026-83858 Chainlit SSRF via Semicolon Path Segment in MCP allowed_urls CVSS 4.0MEDIUM 6.3
  • TI-2026-56755 Chainlit Feedback Endpoints Missing Ownership Validation CVSS 4.0MEDIUM 6.0
  • TI-2026-17829 Chainlit < 2.9.4 SQLAlchemy Data Layer SSRF via /project/element CVSS 4.0HIGH 8.3
  • TI-2026-40492 Chainlit < 2.10.1 Session Hijacking via WebSocket Session Restoration CVSS 4.0HIGH 8.8
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences