CVE-2020-1967
HIGHEPSS 99th pctlDescription
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 v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploit Intelligence
Very high risk: more likely to be exploited than 99% of all known CVEs.
References
- 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%3Ba=commitdiff%3Bh=eb563247aef3e83dda7679c43f9649270462e5b1
- https://github.com/irsl/CVE-2020-1967
- https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44440
- https://lists.apache.org/thread.html/r66ea9c436da150683432db5fbc8beb8ae01886c6459ac30c2cea7345%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r94d6ac3f010a38fccf4f432b12180a13fa1cf303559bd805648c9064%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r9a41e304992ce6aec6585a87842b4f2e692604f5c892c37e3b0587ee%40%3Cdev.tomcat.apache.org%3E
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DDHOAATPWJCXRNFMJ2SASDBBNU5RJONY/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EXDDAOWSAIEFQNBHWYE6PPYFV4QXGMCD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/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/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuApr2021.html
- https://www.oracle.com/security-alerts/cpujan2021.html
- https://www.oracle.com/security-alerts/cpujul2020.html
- https://www.oracle.com/security-alerts/cpuoct2020.html
- https://www.oracle.com/security-alerts/cpuoct2021.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
- https://www.tenable.com/security/tns-2020-11
- https://www.tenable.com/security/tns-2021-10
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Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.