CVE-2025-6855: Langchain-Chatchat · Path Traversal
Affects Langchain-ChatchatSource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 51% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 29 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHubchatchat-space/Langchain-Chatchatpkg:github/chatchat-space/Langchain-ChatchatOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
1. Immediate mitigation should include restricting access to the /v1/file endpoint to trusted and authenticated users only, minimizing exposure to adjacent network attackers. 2. Implement strict input validation and sanitization on the 'flag' parameter to prevent directory traversal sequences such as '../'. 3. Employ web application firewalls (WAFs) with custom rules to detect and block path traversal attempts targeting this endpoint. 4. Monitor logs for unusual file access patterns or attempts to access sensitive directories. 5. Isolate the Langchain-Chatchat service in a hardened environment with minimal file system permissions to limit the impact of any successful traversal. 6. Engage with the vendor or community to obtain patches or updates addressing this vulnerability as soon as they become available. 7. Conduct internal audits and penetration testing focused on this vulnerability to assess exposure and response readiness.
Description
A vulnerability, which was classified as critical, has been found in chatchat-space Langchain-Chatchat up to 0.3.1. This issue affects some unknown processing of the file /v1/file. The manipulation of the argument flag leads to path traversal. The exploit has been disclosed to the public and may be used.