PT-2026-31643 · Unknown · Osslsigncode

Published 2026-04-09 · Updated 2026-04-09 · CVE-2026-39853

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions osslsigncode versions prior to 2.12

Description A stack buffer overflow 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 without validating the source length. This occurs in the verification handlers for PE, MSI, CAB, and script files. A crafted malicious signed file with an oversized digest field can cause an unbounded memcpy to overflow the stack buffer and corrupt stack state.

Recommendations Update osslsigncode to version 2.12 or later.

Fix

Stack Overflow

Memory Corruption

Weakness Enumeration

CWE-121

CWE-787

Related Identifiers

CVE-2026-39853

Affected Products

Osslsigncode

References · 11

• https://github.com/mtrojnar/osslsigncode/commit/cbee1e723c5a8547302bd841ad9943ed8144db68 · Patch
• https://github.com/mtrojnar/osslsigncode/security/advisories/GHSA-hx87-8754-xvh4 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39853 · Security Note
• https://ubuntu.com/security/CVE-2026-39853 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-39853 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-39853 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-39853 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-39853 · Vendor Advisory
• https://github.com/mtrojnar/osslsigncode/releases/tag/2.12 · Note
• https://twitter.com/CVEnew/status/2042302807366308287 · Twitter Post
• https://twitter.com/VulmonFeeds/status/2042290420806197531 · Twitter Post