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Medium ALAS2-2023-2039 3 CVEs

Moderate: openssl11 security update (Amazon Linux 2)

Published May 11, 2023 · Updated May 16, 2023

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2023-0466: The function X509_VERIFY_PARAM_add0_policy() is documented to implicitly enable the certificate policy check when doing certificate verification. However the implementation of the function does not enable the check which allows certificates with invalid or incorrect policies to pass the certificate verification. As suddenly enabling the policy check could break existing deployments it was decided to keep the existing behavior of the X509_VERIFY_PARAM_add0_policy() function. Instead the applications that require OpenSSL to perform certificate policy check need to use X509_VERIFY_PARAM_set1_policies() or explicitly enable the policy check by calling X509_VERIFY_PARAM_set_flags() with the X509_V_FLAG_POLICY_CHECK flag argument. Certificate policy checks are disabled by default in OpenSSL and are not commonly used by applications. CVE-2023-0465: 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. CVE-2023-0464: A security vulnerability has been identified in all supported versions of OpenSSL related to the verification of X.509 certificate chains that include policy constraints. Attackers may be able to exploit this vulnerability by creating a malicious certificate chain that triggers exponential use of computational resources, leading to a denial-of-service (DoS) attack on affected systems. 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.

Fixed packages 5

ReleasePackageFixed in
Amazon Linux · 2 openssl11 1:1.1.1g-12.amzn2.0.14
Amazon Linux · 2 openssl11-debuginfo 1:1.1.1g-12.amzn2.0.14
Amazon Linux · 2 openssl11-devel 1:1.1.1g-12.amzn2.0.14
Amazon Linux · 2 openssl11-libs 1:1.1.1g-12.amzn2.0.14
Amazon Linux · 2 openssl11-static 1:1.1.1g-12.amzn2.0.14

Vulnerabilities 3

  • High 7.5
    CVE-2023-0464 Public exploit

    Excessive Resource Usage Verifying X.509 Policy Constraints

    A security vulnerability has been identified in all supported versions of OpenSSL related to the verification of X.509 certificate chains that include policy constraints. Attackers may be able to exploit this vulnerability by creating a malicious certificate …

  • Medium 5.3

    Invalid certificate policies in leaf certificates are silently ignored

    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 pol…

  • Medium 5.3

    Certificate policy check not enabled

    The function X509_VERIFY_PARAM_add0_policy() is documented to implicitly enable the certificate policy check when doing certificate verification. However the implementation of the function does not enable the check which allows certificates with invalid or in…

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2023-0464.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2023-0465.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2023-0466.html