CVE-2026-42766

CVE Details

Release Date:	2026-06-09
Impact:	Low	What is this?

Description

Issue summary: A specially crafted password-encrypted CMS message can trigger a NULL pointer dereference during CMS decryption. Impact summary: This NULL pointer dereference leads to an application crash and a Denial of Service. The CMS PasswordRecipientInfo.keyDerivationAlgorithm field is defined as OPTIONAL in the ASN.1 specification and may therefore be absent in specially crafted inputs. During the password-based CMS decryption the OpenSSL CMS implementation dereferences this field without first checking whether it was present. An attacker who supplies such a CMS message to an application performing password-based CMS decryption can trigger an application crash, leading to a Denial of Service. Applications that process password-encrypted CMS messages may be affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

See more information about CVE-2026-42766 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	5.3
Vector String:	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Version:	3.1
Attack Vector:	Network
Attack Complexity:	High
Privileges Required:	Low
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	None
Integrity Impact:	None
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (openssl)	ELSA-2026-25239	2026-06-23