CVE-2026-42766
openssl: Possible NULL Dereference in Password-Based CMS Decryption
Severity
LowRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 9, 2026
Updated · October 15, 2026
Description
A flaw was found in OpenSSL. A remote attacker could exploit a NULL pointer dereference vulnerability in the Cryptographic Message Syntax (CMS) decryption process by providing a specially crafted password-encrypted CMS message. This occurs because the keyDerivationAlgorithm field, which is optional, is dereferenced without proper validation. Successful exploitation leads to an application crash, resulting in a Denial of Service.
Statement
This issue is rated as Low impact. A NULL pointer dereference in OpenSSL's CMS decryption can be triggered by a specially crafted password-encrypted CMS message, leading to an Red Hat application crash and Denial of Service. This affects applications that perform password-based CMS decryption.
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 · 5.3CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-476 · NULL Pointer Dereference