OpenSSL patched a high severity vulnerability CVE-2020-1967 in certain OpenSSL versions. As a result, a bad actor could exploit and launch a Denial of Service attack against impacted systems.
OpenSSL described the Segmentation fault in SSL_check_chain (CVE-2020-1967) vulnerability in a recent security advisory:
“Server or client applications that call the SSL_check_chain() function during or after a TLS 1.3 handshake may crash due to a NULL pointer dereference as a result of incorrect handling of the “signature_algorithms_cert” TLS extension. The crash occurs if an invalid or unrecognised signature algorithm is received from the peer. This could be exploited by a malicious peer in a Denial of Service attack.”OpenSSL
In addition, OpenSSL said the vulnerability impacts versions 1.1.1d, 1.1.1e and 1.1.1f.
OpenSSL recommends 1.1.1 users upgrade to the latest version of OpenSSL 1.1.1g.