id: PYSEC-2026-2559
published: "2026-07-13T15:02:57.451046Z"
modified: "2026-07-13T16:04:29.262154Z"
aliases:
- CVE-2026-7846
- GHSA-x229-w2j4-h748
summary: Langchain-Chatchat has a Race Condition in its OpenAI-Compatible File Upload API
details: A vulnerability has been found in chatchat-space Langchain-Chatchat up to 0.3.1.3. Impacted is the function files of the file libs/chatchat-server/chatchat/server/api_server/openai_routes.py of the component OpenAI-Compatible File Upload API. Such manipulation of the argument file.filename leads to time-of-check time-of-use. Access to the local network is required for this attack to succeed. The attack requires a high level of complexity. The exploitability is considered difficult. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.
affected:
- package:
    name: langchain-chatchat
    ecosystem: PyPI
    purl: pkg:pypi/langchain-chatchat
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: "0"
    - last_affected: 0.3.1.3
  versions:
  - 0.3.0
  - 0.3.0.20240506
  - 0.3.0.20240606
  - 0.3.0.20240610
  - 0.3.0.20240610.1
  - 0.3.0.20240611
  - 0.3.0.20240612
  - 0.3.0.20240612.1
  - 0.3.0.20240612.2
  - 0.3.0.20240612.3
  - 0.3.0.20240612.4
  - 0.3.0.20240616
  - 0.3.0.20240618
  - 0.3.0.20240619
  - 0.3.0.20240621
  - 0.3.0.20240621.3
  - 0.3.0.20240625
  - 0.3.0.20240625.1
  - 0.3.1
  - 0.3.1.1
  - 0.3.1.2
  - 0.3.1.3
references:
- type: ADVISORY
  url: https://nvd.nist.gov/vuln/detail/CVE-2026-7846
- type: WEB
  url: https://github.com/chatchat-space/Langchain-Chatchat/issues/5463
- type: WEB
  url: https://github.com/3em0/cve_repo/blob/main/Langchain-Chatchat/Vuln-2-Silent-File-Overwrite.md
- type: PACKAGE
  url: https://github.com/chatchat-space/Langchain-Chatchat
- type: WEB
  url: https://vuldb.com/submit/807795
- type: WEB
  url: https://vuldb.com/vuln/361125
- type: WEB
  url: https://vuldb.com/vuln/361125/cti
- type: PACKAGE
  url: https://pypi.org/project/langchain-chatchat
- type: ADVISORY
  url: https://github.com/advisories/GHSA-x229-w2j4-h748
severity:
- type: CVSS_V3
  score: CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
- type: CVSS_V4
  score: CVSS:4.0/AV:A/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P