Detections
Analytics
CVE-2020-1967
high
Description
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 version 1.1.1d, 1.1.1e, and 1.1.1f are affected by this issue. This issue did not affect OpenSSL versions prior to 1.1.1d. Fixed in OpenSSL 1.1.1g (Affected 1.1.1d-1.1.1f).
References
https://www.tenable.com/security/tns-2021-10
https://www.tenable.com/security/tns-2020-11
https://www.tenable.com/security/tns-2020-04
https://www.tenable.com/security/tns-2020-03
https://www.synology.com/security/advisory/Synology_SA_20_05_OpenSSL
https://www.synology.com/security/advisory/Synology_SA_20_05
https://www.oracle.com/security-alerts/cpuoct2021.html
https://www.oracle.com/security-alerts/cpuoct2020.html
https://www.oracle.com/security-alerts/cpujul2020.html
https://www.oracle.com/security-alerts/cpujan2021.html
https://www.oracle.com/security-alerts/cpuApr2021.html
https://www.oracle.com//security-alerts/cpujul2021.html
https://www.debian.org/security/2020/dsa-4661
https://security.netapp.com/advisory/ntap-20200717-0004/
https://security.netapp.com/advisory/ntap-20200424-0003/
https://security.gentoo.org/glsa/202004-10
https://security.FreeBSD.org/advisories/FreeBSD-SA-20:11.openssl.asc
https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44440
http://www.openwall.com/lists/oss-security/2020/04/22/2
http://seclists.org/fulldisclosure/2020/May/5
http://packetstormsecurity.com/files/157527/OpenSSL-signature_algorithms_cert-Denial-Of-Service.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00011.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00004.html