CVE-2026-42769

Issue Summary: An error in the callback used to verify the certificate provided in a Root CA key update Certificate Management Protocol (CMP) message response rendered the certificate validation ineffectual, which could lead to escalation of credentials from the Registration Authority (RA) level to the root Certification Authority (root CA) level. Impact Summary: The Registration Autority could replace the root CA certificate for the CMP clients with an arbitrary root CA certificate. One of the parts of the Certificate Management Protocol (CMP), specified in RFC 9810, is Root Certification Authority (root CA) key Rollover, which is sent by the server in a message with type 'id-it-rootCaKeyUpdate'. As part of these messages, 'newWithOld' certificate, the new root CA certificate signed with the old root CA key, is provided, and verifying its signature is crucial for transferring the trust from the old CA key to the new one. The 'id-it-rootCaKeyUpdate' messages are expected to be processed with OSSL_CMP_get1_rootCaKeyUpdate(), that is expected to verify the 'newWithOld' certificate. A typo in the certificate chain building code led to adding an incorrect certificate ('newWithOld' instead of 'oldRoot') to the certificate chain, rendering the certificate verification process ineffectual (only the issuer name and the algorithm OIDs were verified by other parts of the verification code). An attacker who already has credentials that satisfy the CMP message protection checks can generate a new key pair and use a crafted self-signed certificate in its 'id-it-rootCaKeyUpdate' CMP messages which affected CMP clients would accept as a new trust anchor. Significant preconditions for the attack (having valid RA-level credentials) are the reason the issue was assigned Low severity. The FIPS modules are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.
Configurations

No configuration.

History

10 Jun 2026, 08:16

Type Values Removed Values Added
References
  • {'url': 'https://github.com/openssl/security/commit/54d0989997e5fc26057009a9782c3441ce3842fb', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/777b363b16fcf2153bb3ded39dc3838713667c44', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/d35cd473a271bf3ce7bf3d32af53217fb83ae92c', 'source': 'openssl-security@openssl.org'}
  • {'url': 'https://github.com/openssl/security/commit/d531f21c0fe99067a66fc0ff1161ef127f9cd70b', 'source': 'openssl-security@openssl.org'}
  • () https://github.com/openssl/openssl/commit/54d0989997e5fc26057009a9782c3441ce3842fb -
  • () https://github.com/openssl/openssl/commit/777b363b16fcf2153bb3ded39dc3838713667c44 -
  • () https://github.com/openssl/openssl/commit/d35cd473a271bf3ce7bf3d32af53217fb83ae92c -
  • () https://github.com/openssl/openssl/commit/d531f21c0fe99067a66fc0ff1161ef127f9cd70b -

09 Jun 2026, 21:17

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.3

09 Jun 2026, 17:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-06-09 17:17

Updated : 2026-06-10 08:16


NVD link : CVE-2026-42769

Mitre link : CVE-2026-42769

CVE.ORG link : CVE-2026-42769


JSON object : View

Products Affected

No product.

CWE
CWE-295

Improper Certificate Validation