CVE-2026-42766

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-42766
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.

5.9 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://github.com/openssl/openssl/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199ce Patch
https://github.com/openssl/openssl/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4 Patch
https://github.com/openssl/openssl/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7 Patch
https://github.com/openssl/openssl/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4 Patch
https://github.com/openssl/openssl/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8 Patch
https://openssl-library.org/news/secadv/20260609.txt Vendor Advisory
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*
History

23 Jul 2026, 08:10

Type Values Removed Values Added
Summary
  • (es) Resumen del problema: Un mensaje CMS cifrado con contraseña especialmente diseñado puede desencadenar una desreferencia de puntero NULL durante el descifrado CMS. Resumen del impacto: Esta desreferencia de puntero NULL conduce a un fallo de la aplicación y a una denegación de servicio. El campo CMS PasswordRecipientInfo.keyDerivationAlgorithm se define como OPCIONAL en la especificación ASN.1 y, por lo tanto, puede estar ausente en entradas especialmente diseñadas. Durante el descifrado CMS basado en contraseña, la implementación CMS de OpenSSL desreferencia este campo sin comprobar primero si estaba presente. Un atacante que suministra un mensaje CMS de este tipo a una aplicación que realiza el descifrado CMS basado en contraseña puede desencadenar un fallo de la aplicación, lo que lleva a una denegación de servicio. Las aplicaciones que procesan mensajes CMS cifrados con contraseña pueden verse afectadas. Los módulos FIPS en 4.0, 3.6, 3.5, 3.4 y 3.0 no se ven afectados por este problema, ya que el código afectado está fuera del límite del módulo FIPS de OpenSSL.

15 Jun 2026, 18:25

Type Values Removed Values Added
First Time Openssl openssl
Openssl
CPE cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
References () https://github.com/openssl/openssl/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199ce - () https://github.com/openssl/openssl/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199ce - Patch
References () https://github.com/openssl/openssl/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4 - () https://github.com/openssl/openssl/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4 - Patch
References () https://github.com/openssl/openssl/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7 - () https://github.com/openssl/openssl/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7 - Patch
References () https://github.com/openssl/openssl/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4 - () https://github.com/openssl/openssl/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4 - Patch
References () https://github.com/openssl/openssl/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8 - () https://github.com/openssl/openssl/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8 - Patch
References () https://openssl-library.org/news/secadv/20260609.txt - () https://openssl-library.org/news/secadv/20260609.txt - Vendor Advisory

10 Jun 2026, 08:16

Type Values Removed Values Added
References
  • {'url': 'https://github.com/openssl/security/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199ce', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8', 'source': 'openssl-security@openssl.org'}
  • () https://github.com/openssl/openssl/commit/056d06c1918fafbb98c1c85a02e4c47cc4e199ce -
  • () https://github.com/openssl/openssl/commit/12bc26ffb3a2be728c9b86e1cae277de5b33dfa4 -
  • () https://github.com/openssl/openssl/commit/3ff64913615d648cfbb6a6f1cf5529ae7ea829d7 -
  • () https://github.com/openssl/openssl/commit/ab52d88cb5374876d59aee3c91f9e4ccce2b7ce4 -
  • () https://github.com/openssl/openssl/commit/da26f368732b83e40e9d356fe61c3d3aaab6d2e8 -

09 Jun 2026, 21:17

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.9

09 Jun 2026, 17:17

Type Values Removed Values Added
New CVE
Information

Published : 2026-06-09 17:17

Updated : 2026-07-23 08:10

NVD link : CVE-2026-42766

Mitre link : CVE-2026-42766

CVE.ORG link : CVE-2026-42766

JSON object : View

Products Affected

openssl

  • openssl
CWE
CWE-476

NULL Pointer Dereference