PYSEC-2026-2558

Vulnerability from pysec - Published: 2026-07-13 15:02 - Updated: 2026-07-13 16:04
VLAI
Details

A flaw has been found in chatchat-space Langchain-Chatchat up to 0.3.1.3. This issue affects the function PIL.Image.tobytes of the file libs/chatchat-server/chatchat/webui_pages/dialogue/dialogue.py of the component Vision Chat Paste Image Handler. This manipulation of the argument paste_image.image_data causes use of weak hash. The attacker needs to be present on the local network. The attack is considered to have high complexity. The exploitability is assessed as difficult. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.

Severity
2.6 (Low)
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
1.2 (Low)
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
Impacted products
Name purl
langchain-chatchat pkg:pypi/langchain-chatchat
Aliases
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "langchain-chatchat",
        "purl": "pkg:pypi/langchain-chatchat"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "0.3.1.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "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"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-7845",
    "GHSA-wmvv-fhm6-w34x"
  ],
  "details": "A flaw has been found in chatchat-space Langchain-Chatchat up to 0.3.1.3. This issue affects the function PIL.Image.tobytes of the file libs/chatchat-server/chatchat/webui_pages/dialogue/dialogue.py of the component Vision Chat Paste Image Handler. This manipulation of the argument paste_image.image_data causes use of weak hash. The attacker needs to be present on the local network. The attack is considered to have high complexity. The exploitability is assessed as difficult. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.",
  "id": "PYSEC-2026-2558",
  "modified": "2026-07-13T16:04:29.197675Z",
  "published": "2026-07-13T15:02:57.378714Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-7845"
    },
    {
      "type": "WEB",
      "url": "https://github.com/chatchat-space/Langchain-Chatchat/issues/5462"
    },
    {
      "type": "WEB",
      "url": "https://github.com/3em0/cve_repo/blob/main/Langchain-Chatchat/Vuln-1-tobytes-Hash-Collision.md"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/chatchat-space/Langchain-Chatchat"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/submit/807794"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/361124"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/361124/cti"
    },
    {
      "type": "PACKAGE",
      "url": "https://pypi.org/project/langchain-chatchat"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-wmvv-fhm6-w34x"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Langchain-Chatchat Uses a Broken or Risky Cryptographic Algorithm"
}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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