CVE-2026-45447
openssl: Heap Use-After-Free in OpenSSL PKCS7_verify()
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 9, 2026
Updated · November 4, 2026
Description
A flaw was found in OpenSSL. When processing a specially crafted PKCS#7 or S/MIME (Secure/Multipurpose Internet Mail Extensions) signed message, a heap use-after-free vulnerability in the PKCS7_verify() function can be triggered. This occurs if the SignedData digestAlgorithms field is present as an empty ASN.1 SET, leading to incorrect memory deallocation. A remote attacker could exploit this to cause application crashes, memory corruption, or potentially achieve remote code execution.
Statement
This High severity heap use-after-free flaw in OpenSSL's PKCS7_verify() function can be triggered by processing a specially crafted PKCS#7 or S/MIME signed message. This could lead to application crashes, memory corruption, or potentially remote code execution, impacting services that handle such messages. The vulnerability specifically affects applications utilizing OpenSSL PKCS#7 APIs, while those using CMS APIs are not impacted.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
CVSS / CWE
CVSS 3.1 · 8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-825 · Expired Pointer Dereference