UBUNTU-CVE-2026-39853 (CVE-2026-39853)
Vulnerability from osv_ubuntu – Published: 2026-04-09 16:16 – Updated: 2026-04-16 09:13 – Source website
VLAI
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)
N/A (UNKNOWN)
{
"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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vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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