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Improper Certificate Validation

CVE-2023-0465

Severity Medium
Score 5.3/10

Summary

Applications that use a non-default option when verifying certificates may be vulnerable to an attack from a malicious CA to circumvent certain checks. Invalid certificate policies in leaf certificates are silently ignored by OpenSSL and other certificate policy checks are skipped for that certificate. A malicious CA could use this to deliberately assert invalid certificate policies in order to circumvent policy checking on the certificate altogether. Policy processing is disabled by default but can be enabled by passing the "-policy" argument to the command line utilities or by calling the "X509_VERIFY_PARAM_set1_policies()" function. This issue affects openssl versions 1.0.2x prior to 1.0.2zh, 1.1.1x prior to 1.1.1u, 3.0.0x prior to 3.0.9, and 3.1.0x prior to 3.1.1.

  • LOW
  • NETWORK
  • LOW
  • UNCHANGED
  • NONE
  • NONE
  • NONE
  • NONE

CWE-295 - Improper Certificate Validation

The authenticity component of a web system stems from the ability to validate “Digital certificates”, which (i) establish trust between two or more entities sharing data over a network; (ii) ensure data at rest and transit is secure from unauthorized access; and (iii) check the identity of the actors that interact with the system. An application with absent or ineffective certificate validation mechanisms allows malicious users, impersonating trusted hosts, to manipulate the communication path between the client and the host, resulting in unauthorized access to data and to the application’s internal environment, and potentially enabling man-in-the-middle attacks.

Advisory Timeline

  • Published