UBUNTU-CVE-2026-94184 (CVE-2026-94184)

Vulnerability from osv_ubuntu – Published: 2026-09-21 15:17 – Updated: 2026-09-25 03:50 – Source website
VLAI
Details

A stack-based buffer overflow flaw was found in fetchmail when built with NTLM support. A malicious or compromised mail server advertising NTLM authentication can send a crafted Type 2 challenge that causes fetchmail to write past a fixed stack buffer while building the NTLM authenticate response. This may lead to remote code execution depending on stack-frame layout, or to authentication failure or process termination under memory hardening. Affects v5.0.8 through v6.6.6.

Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fetchmail",
            "binary_version": "6.3.26-2"
          },
          {
            "binary_name": "fetchmailconf",
            "binary_version": "6.3.26-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "fetchmail",
        "purl": "pkg:deb/ubuntu/fetchmail@6.3.26-2?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.3.26-1",
        "6.3.26-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fetchmail",
            "binary_version": "6.3.26-3ubuntu0.1~18.04.1"
          },
          {
            "binary_name": "fetchmailconf",
            "binary_version": "6.3.26-3ubuntu0.1~18.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "fetchmail",
        "purl": "pkg:deb/ubuntu/fetchmail@6.3.26-3ubuntu0.1~18.04.1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.3.26-3",
        "6.3.26-3build1",
        "6.3.26-3ubuntu0.1~18.04.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fetchmail",
            "binary_version": "6.4.2-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "fetchmail",
        "purl": "pkg:deb/ubuntu/fetchmail@6.4.2-2?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.4.0~rc4-1ubuntu1",
        "6.4.1-1ubuntu1",
        "6.4.2-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fetchmail",
            "binary_version": "6.4.27-1ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "fetchmail",
        "purl": "pkg:deb/ubuntu/fetchmail@6.4.27-1ubuntu0.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.4.22-1",
        "6.4.23-1",
        "6.4.24-1",
        "6.4.25-1",
        "6.4.26-1",
        "6.4.27-1",
        "6.4.27-1ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fetchmail",
            "binary_version": "6.4.38-1ubuntu4.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "fetchmail",
        "purl": "pkg:deb/ubuntu/fetchmail@6.4.38-1ubuntu4.1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.4.37-1",
        "6.4.38-1ubuntu1",
        "6.4.38-1ubuntu3",
        "6.4.38-1ubuntu4",
        "6.4.38-1ubuntu4.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fetchmail",
            "binary_version": "6.6.2-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "fetchmail",
        "purl": "pkg:deb/ubuntu/fetchmail@6.6.2-2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.5.4-0ubuntu2",
        "6.5.4-0ubuntu3",
        "6.6.2-2"
      ]
    }
  ],
  "aliases": [],
  "details": "A stack-based buffer overflow flaw was found in fetchmail when built with NTLM support. A malicious or compromised mail server advertising NTLM authentication can send a crafted Type 2 challenge that causes fetchmail to write past a fixed stack buffer while building the NTLM authenticate response. This may lead to remote code execution depending on stack-frame layout, or to authentication failure or process termination under memory hardening. Affects v5.0.8 through v6.6.6.",
  "id": "UBUNTU-CVE-2026-94184",
  "modified": "2026-09-25T03:50:06Z",
  "published": "2026-09-21T15:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-94184"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-94184"
    },
    {
      "type": "REPORT",
      "url": "https://www.fetchmail.info/fetchmail-SA-2026-01.txt"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-94184"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2026/06/27/8"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-94184"
  ]
}



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