NULL pointer dereference in OpenSSL - CVE-2026-42766
Published: June 10, 2026
Vulnerability identifier: #VU134281
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-42766
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: OpenSSL Software Foundation
Affected software:
OpenSSL
OpenSSL
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to NULL pointer dereference in password-based CMS decryption when processing a specially crafted CMS message with an absent PasswordRecipientInfo.keyDerivationAlgorithm field. A remote attacker can send a specially crafted CMS message to cause a denial of service.
Applications that process password-encrypted CMS messages may be affected.
How to mitigate CVE-2026-42766
Install security update from vendor's website.