CVE-2022-3786: OpenSSL3 CVE-2022-3602 CVE-2022-3786 vulnerabilities

A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed a malicious certificate or for an application to continue certificate verification despite failure to construct a path to a trusted issuer. An attacker can craft a malicious email address in a certificate to overflow an arbitrary number of bytes containing the .' character (decimal 46) on the stack. This buffer overflow could result in a crash (causing a denial of service). In a TLS client, this can be triggered by connecting to a malicious server. In a TLS server, this can be triggered if the server requests client authentication and a malicious client connects.

As per upstream report:

A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed the malicious certificate or for the application to continue certificate verification despite failure to construct a path to a trusted issuer. An attacker can craft a malicious email address to overflow an arbitrary number of bytes containing the .' character (decimal 46) on the stack. This buffer overflow could result in a crash (causing a denial of service).

In a TLS client, this can be triggered by connecting to a malicious server. In a TLS server, this can be triggered if the server requests client authentication and a malicious client connects.

OpenSSL versions 3.0.0 to 3.0.6 are vulnerable to this issue.

OpenSSL 3.0 users should upgrade to OpenSSL 3.0.7.

OpenSSL 1.1.1 and 1.0.2 are not affected by this issue.

— Red Hat

OpenSSL is vulnerable to a denial of service, caused by a stack based buffer overflow during X.509 certificate verification. By using a specially-crafted email address in a certificate, a remote attacker could exploit this vulnerability to cause a TLS client to crash, and results in a denial of service condition.

— IBM