osslsigncode — security advisory
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.
- Products
- osslsigncode
- Affected versions
- 2.10-1, 2.11-1, 2.12-1, 2.13-1, 2.13-2, 2.14-1, 2.5-4, 2.8-1, 2.8-2, 2.9-1, 2.9-1~bpo12+1, 2.9-2
- Fixed versions
- 2.12-1
- CVEs
- CVE-2026-39853
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:37 UTC · Revision 2
Source evidence
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.
osv:DEBIAN-CVE-2026-39853
osslsigncode
Fixed versions: Not specified
osslsigncode
Fixed versions: Not specified
osslsigncode
Fixed versions: 2.12-1
Complete source record
{
"id": "db8a82a0f1eeee0be93185e07ec53e6a12676544a5d6f4a4f331baf5cefa6a95",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-39853",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-39853",
"summary": "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.",
"evidence": "osv:DEBIAN-CVE-2026-39853",
"products": [
{
"name": {
"value": "osslsigncode",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.11-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.12-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.13-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.13-2",
"evidence": "/affected/0/versions"
},
{
"value": "2.14-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.5-4",
"evidence": "/affected/0/versions"
},
{
"value": "2.8-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.8-2",
"evidence": "/affected/0/versions"
},
{
"value": "2.9-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.9-1~bpo12+1",
"evidence": "/affected/0/versions"
},
{
"value": "2.9-2",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "osslsigncode",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.11-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.12-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.13-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.13-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.14-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.9-2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "osslsigncode",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.12-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "2.10-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.11-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.9-2",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-39853",
"aliases": [
"DEBIAN-CVE-2026-39853"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "osslsigncode",
"purl": "pkg:deb/debian/osslsigncode?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.10-1",
"2.11-1",
"2.12-1",
"2.13-1",
"2.13-2",
"2.14-1",
"2.5-4",
"2.8-1",
"2.8-2",
"2.9-1",
"2.9-1~bpo12+1",
"2.9-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39853.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "osslsigncode",
"purl": "pkg:deb/debian/osslsigncode?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.10-1",
"2.11-1",
"2.12-1",
"2.13-1",
"2.13-2",
"2.14-1",
"2.9-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39853.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.12-1"
}
]
}
],
"package": {
"name": "osslsigncode",
"purl": "pkg:deb/debian/osslsigncode?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.10-1",
"2.11-1",
"2.9-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39853.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-27T09:47:29.725708556Z",
"provider": "osv",
"upstream": [
"CVE-2026-39853"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-39853"
]
},
"related_cves": [
{
"value": "CVE-2026-39853",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 460914,
"published_at": "2026-04-09T16:16:31.233+00:00"
}