CVE-2026-42766 Affecting openssl package, versions <3.5.7-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.6% (44th percentile)

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  • Snyk IDSNYK-ALPINE324-OPENSSL-17304674
  • published11 Jun 2026
  • disclosed9 Jun 2026

Introduced: 9 Jun 2026

NewCVE-2026-42766  (opens in a new tab)

How to fix?

Upgrade Alpine:3.24 openssl to version 3.5.7-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream openssl package and not the openssl package as distributed by Alpine. See How to fix? for Alpine:3.24 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1