ubuntu-cve-2026-39853
Vulnerability from osv_ubuntu
Published
2026-04-09 16:16
Modified
2026-04-16 09:13
Summary
Details

osslsigncode is a tool that implements Authenticode signing and timestamping. Prior to 2.12, A stack buffer overflow vulnerability exists in osslsigncode in several signature verification paths. During verification of a PKCS#7 signature, the code copies the digest value from a parsed SpcIndirectDataContent structure into a fixed-size stack buffer (mdbuf[EVP_MAX_MD_SIZE], 64 bytes) without validating that the source length fits within the destination buffer. This pattern is present in the verification handlers for PE, MSI, CAB, and script files. An attacker can craft a malicious signed file with an oversized digest field in SpcIndirectDataContent. When a user verifies such a file with osslsigncode verify, the unbounded memcpy can overflow the stack buffer and corrupt adjacent stack state. This vulnerability is fixed in 2.12.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "osslsigncode",
            "binary_version": "1.7.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "osslsigncode",
        "purl": "pkg:deb/ubuntu/osslsigncode@1.7.1-1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.7.1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "osslsigncode",
            "binary_version": "1.7.1-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "osslsigncode",
        "purl": "pkg:deb/ubuntu/osslsigncode@1.7.1-3?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.7.1-2build1",
        "1.7.1-2ubuntu1",
        "1.7.1-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "osslsigncode",
            "binary_version": "2.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "osslsigncode",
        "purl": "pkg:deb/ubuntu/osslsigncode@2.0-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "osslsigncode",
            "binary_version": "2.2-1ubuntu1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "osslsigncode",
        "purl": "pkg:deb/ubuntu/osslsigncode@2.2-1ubuntu1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.1-1",
        "2.2-1ubuntu1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "osslsigncode",
            "binary_version": "2.8-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "osslsigncode",
        "purl": "pkg:deb/ubuntu/osslsigncode@2.8-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.5-4",
        "2.8-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "osslsigncode",
            "binary_version": "2.9-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "osslsigncode",
        "purl": "pkg:deb/ubuntu/osslsigncode@2.9-2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.9-2"
      ]
    }
  ],
  "aliases": [],
  "details": "osslsigncode is a tool that implements Authenticode signing and timestamping. Prior to 2.12, A stack buffer overflow vulnerability exists in osslsigncode in several signature verification paths. During verification of a PKCS#7 signature, the code copies the digest value from a parsed SpcIndirectDataContent structure into a fixed-size stack buffer (mdbuf[EVP_MAX_MD_SIZE], 64 bytes) without validating that the source length fits within the destination buffer. This pattern is present in the verification handlers for PE, MSI, CAB, and script files. An attacker can craft a malicious signed file with an oversized digest field in SpcIndirectDataContent. When a user verifies such a file with osslsigncode verify, the unbounded memcpy can overflow the stack buffer and corrupt adjacent stack state. This vulnerability is fixed in 2.12.",
  "id": "UBUNTU-CVE-2026-39853",
  "modified": "2026-04-16T09:13:14Z",
  "published": "2026-04-09T16:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-39853"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-39853"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/mtrojnar/osslsigncode/security/advisories/GHSA-hx87-8754-xvh4"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/mtrojnar/osslsigncode/commit/cbee1e723c5a8547302bd841ad9943ed8144db68"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/mtrojnar/osslsigncode/releases/tag/2.12"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-39853"
  ]
}



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