CVE-2020-1967 Information
Share on: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).
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Reference
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00004.html http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00011.html http://packetstormsecurity.com/files/157527/OpenSSL-signature_algorithms_cert-Denial-Of-Service.html http://seclists.org/fulldisclosure/2020/May/5 http://www.openwall.com/lists/oss-security/2020/04/22/2 https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=eb563247aef3e83dda7679c43f9649270462e5b1 https://github.com/irsl/CVE-2020-1967 https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44440 https://lists.apache.org/thread.html/r66ea9c436da150683432db5fbc8beb8ae01886c6459ac30c2cea7345@3Cdev.tomcat.apache.org3E https://lists.apache.org/thread.html/r94d6ac3f010a38fccf4f432b12180a13fa1cf303559bd805648c9064@3Cdev.tomcat.apache.org3E https://lists.apache.org/thread.html/r9a41e304992ce6aec6585a87842b4f2e692604f5c892c37e3b0587ee@3Cdev.tomcat.apache.org3E https://lists.fedoraproject.org/archives/list/[email protected]/message/DDHOAATPWJCXRNFMJ2SASDBBNU5RJONY/ https://lists.fedoraproject.org/archives/list/[email protected]/message/EXDDAOWSAIEFQNBHWYE6PPYFV4QXGMCD/ https://lists.fedoraproject.org/archives/list/[email protected]/message/XVEP3LAK4JSPRXFO4QF4GG2IVXADV3SO/ https://security.FreeBSD.org/advisories/FreeBSD-SA-20:11.openssl.asc https://security.gentoo.org/glsa/202004-10 https://security.netapp.com/advisory/ntap-20200424-0003/ https://security.netapp.com/advisory/ntap-20200717-0004/ https://www.debian.org/security/2020/dsa-4661 https://www.openssl.org/news/secadv/20200421.txt https://www.oracle.com/security-alerts/cpujul2020.html https://www.oracle.com/security-alerts/cpuoct2020.html https://www.synology.com/security/advisory/Synology_SA_20_05 https://www.synology.com/security/advisory/Synology_SA_20_05_OpenSSL https://www.tenable.com/security/tns-2020-03 https://www.tenable.com/security/tns-2020-04
Attack Complexity
LOW
Privileges Required
NONE
User Interaction Required
NONE
Scope
NONE
Confidentiality Impact
UNCHANGED
Integrity Impact
NONE
Availability Impact
NONE
Base Score
HIGH
Base Severity
7.5