CVE-2025-6855: Langchain chatchat Path Traversal Vulnerability

LOW
Advisory Identifier: GHSA-f823-phmg-x5fr
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CVSS 5.5
CWE-22
Published
Advisory Summary

CVE-2025-6855 is a LOW (CVSS 5.5) path traversal vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting Langchain chatchat libraries in the PyPI ecosystem. The issue involves langchain-chatchat vulnerable to path traversal. Remediation is available in the latest vendor maintenance releases.

CVE-2025-6855 at a Glance

CVE Identifier CVE-2025-6855
GHSA Identifier GHSA-f823-phmg-x5fr
Severity LOW
CVSS v3.1 Base Score 5.5
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product Langchain chatchat
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 5.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L).

Attack Vector Adjacent (AV:A)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2025-6855

To remediate this vulnerability, upgrade all affected Langchain chatchat dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

langchain-chatchat fixed: Latest secure release 
pip install langchain-chatchat>=Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show langchain-chatchat

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2025-6855, inspect your installed packages using pip:

pip show langchain-chatchat

Analyze the terminal output to locate any version of Langchain chatchat in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The pip show langchain-chatchat command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'), where the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. In Langchain chatchat, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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.

CVE-2025-6855 Affected Langchain chatchat Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
langchain-chatchat
pypi/langchain-chatchat
PyPI
≤ 0.3.1

References

NVD — CVE-2025-6855 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-6855
Langchain chatchat Source Repository REPOSITORY
https://github.com/chatchat-space/Langchain-Chatchat/issues/5354
Langchain chatchat Source Repository REPOSITORY
https://github.com/chatchat-space/Langchain-Chatchat
vuldb.com/ WEB
https://vuldb.com/?ctiid.314327
vuldb.com/ WEB
https://vuldb.com/?id.314327
vuldb.com/ WEB
https://vuldb.com/?submit.601162

Frequently Asked Questions

What is CVE-2025-6855?
CVE-2025-6855 is a security vulnerability in Langchain chatchat involving Langchain-Chatchat vulnerable to path traversal under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which Langchain chatchat versions are affected?
Affected versions include releases prior to current release patches across affected packages: langchain-chatchat.
What version fixes CVE-2025-6855?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is langchain-chatchat affected?
Yes, langchain-chatchat is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2025-6855?
CVE-2025-6855 has a CVSS v3.1 base score of 5.5 (LOW) with vector string CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.
What CWE is associated with CVE-2025-6855?
CVE-2025-6855 is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.).
How can I check PyPI dependencies for CVE-2025-6855?
Run the dependency tree command: 'pip show langchain-chatchat'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f823-phmg-x5fr",
  "modified" : "2025-11-03T20:14:59Z",
  "published" : "2025-06-29T09:30:23Z",
  "aliases" : [ "CVE-2025-6855" ],
  "summary" : "Langchain-Chatchat vulnerable to path traversal",
  "details" : "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.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "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:P"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "langchain-chatchat"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.3.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-6855"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/chatchat-space/Langchain-Chatchat/issues/5354"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/chatchat-space/Langchain-Chatchat"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?ctiid.314327"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?id.314327"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?submit.601162"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-11-03T20:14:58Z",
    "nvd_published_at" : "2025-06-29T09:15:24Z"
  }
}