Broadcom API Gateway: OpenSSL vulnerabilities CVE-2023-0465 and CVE-2023-0466

Products

• CA API Gateway

Issue/Introduction

OpenSSL versions 1.0.2 and 1.1.1 are affected by the following vulnerabilities:

CVE-2023-0465  Reference: https://nvd.nist.gov/vuln/detail/CVE-2023-0465

CVE-2023-0466  Reference: https://nvd.nist.gov/vuln/detail/CVE-2023-0466 

Appliance Gateway 10.1 uses OpenSSL 1.0.2 and Appliance Gateway 11.0 uses OpenSSL 1.1.1.

Can the Gateway be affected?

Environment

API Gateway 

Cause

Both CVEs, do target the Certificate validation policy check to exploit a victim, specifically:

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-2023-0466: 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.

Resolution

The methods used to exploit are not applicable since Gateway does not use OpenSSL. We instead use Java-based TLS providers embedded in the product.

Hence the Gateway is not directly affected. Monthly Platform Update patches will provide adequate maintenance to OpenSSL when required. Hence keeping the platform under regular maintenance is recommended.