{"id":"CVE-2020-1971","url":"https://www.cyber-defence.io/tools/cve/CVE-2020-1971","generatedAt":"2026-10-27T22:24:38.631Z","title":"A NULL pointer dereference and a crash may occur leading to a possible denial of service attack.","description":"The X.509 GeneralName type is a generic type for representing different types of names. One of those name types is known as EDIPartyName. OpenSSL provides a function GENERAL_NAME_cmp which compares different instances of a GENERAL_NAME to see if they are equal or not. This function behaves incorrectly when both GENERAL_NAMEs contain an EDIPARTYNAME. A NULL pointer dereference and a crash may occur leading to a possible denial of service attack. OpenSSL itself uses the GENERAL_NAME_cmp function for two purposes: 1) Comparing CRL distribution point names between an available CRL and a CRL distribution point embedded in an X509 certificate 2) When verifying that a timestamp response token signer matches the timestamp authority name (exposed via the API functions TS_RESP_verify_response and TS_RESP_verify_token) If an attacker can control both items being compared then that attacker could trigger a crash. For example if the attacker can trick a client or server into checking a malicious certificate against a malicious CRL then this may occur. Note that some applications automatically download CRLs based on a URL embedded in a certificate. This checking happens prior to the signatures on the certificate and CRL being verified. OpenSSL's s_server, s_client and verify tools have support for the \"-crl_download\" option which implements automatic CRL downloading and this attack has been demonstrated to work against those tools. Note that an unrelated bug means that affected versions of OpenSSL cannot parse or construct correct encodings of EDIPARTYNAME. However it is possible to construct a malformed EDIPARTYNAME that OpenSSL's parser will accept and hence trigger this attack. All OpenSSL 1.1.1 and 1.0.2 versions are affected by this issue. Other OpenSSL releases are out of support and have not been checked. Fixed in OpenSSL 1.1.1i (Affected 1.1.1-1.1.1h). Fixed in OpenSSL 1.0.2x (Affected 1.0.2-1.0.2w).","published":"2020-12-08T16:15:12.000Z","lastModified":"2026-06-17T03:02:45.000Z","status":"Modified","sourceIdentifier":"openssl-security@openssl.org","cvss":{"version":"3.1","score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-476"],"affected":["openssl/openssl","debian/debian linux","fedoraproject/fedora","oracle/api gateway","oracle/business intelligence","oracle/communications cloud native core network function cloud native environment","oracle/communications diameter intelligence hub","oracle/communications session border controller","oracle/communications session router","oracle/communications subscriber-aware load balancer","oracle/communications unified session manager","oracle/enterprise communications broker","oracle/enterprise manager base platform","oracle/enterprise manager for storage management","oracle/enterprise manager ops center","oracle/enterprise session border controller","oracle/essbase","oracle/graalvm","oracle/http server","oracle/jd edwards enterpriseone tools","oracle/jd edwards world security","oracle/mysql","oracle/mysql server","oracle/peoplesoft enterprise peopletools","netapp/active iq unified manager","netapp/clustered data ontap antivirus connector","netapp/data ontap","netapp/e-series santricity os controller","netapp/hci management node","netapp/manageability software development kit","netapp/oncommand insight","netapp/oncommand workflow automation","netapp/plug-in for symantec netbackup","netapp/santricity smi-s provider","netapp/snapcenter","netapp/solidfire","netapp/hci compute node","netapp/hci storage node","netapp/ef600a firmware","netapp/aff a250 firmware","tenable/log correlation engine","tenable/nessus network monitor","siemens/sinec infrastructure network services","nodejs/node.js"],"epss":{"score":0.06994,"percentile":0.94113,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (6.99%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"http://www.openwall.com/lists/oss-security/2021/09/14/2","tags":["Mailing List","Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=2154ab83e14ede338d2ede9bbe5cdfce5d5a6c9e","source":"openssl-security@openssl.org"},{"url":"https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=f960d81215ebf3f65e03d4d5d857fb9b666d6920","source":"openssl-security@openssl.org"},{"url":"https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44676","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://lists.apache.org/thread.html/r63c6f2dd363d9b514d0a4bcf624580616a679898cc14c109a49b750c%40%3Cdev.tomcat.apache.org%3E","source":"openssl-security@openssl.org"},{"url":"https://lists.apache.org/thread.html/rbb769f771711fb274e0a4acb1b5911c8aab544a6ac5e8c12d40c5143%40%3Ccommits.pulsar.apache.org%3E","source":"openssl-security@openssl.org"},{"url":"https://lists.debian.org/debian-lts-announce/2020/12/msg00020.html","tags":["Mailing List","Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://lists.debian.org/debian-lts-announce/2020/12/msg00021.html","tags":["Mailing List","Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DGSI34Y5LQ5RYXN4M2I5ZQT65LFVDOUU/","source":"openssl-security@openssl.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PWPSSZNZOBJU2YR6Z4TGHXKYW3YP5QG7/","source":"openssl-security@openssl.org"},{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-20:33.openssl.asc","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://security.gentoo.org/glsa/202012-13","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://security.netapp.com/advisory/ntap-20201218-0005/","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://security.netapp.com/advisory/ntap-20210513-0002/","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://security.netapp.com/advisory/ntap-20240621-0006/","source":"openssl-security@openssl.org"},{"url":"https://www.debian.org/security/2020/dsa-4807","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.openssl.org/news/secadv/20201208.txt","tags":["Vendor Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","tags":["Patch","Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.oracle.com/security-alerts/cpuApr2021.html","tags":["Patch","Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["Patch","Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.oracle.com/security-alerts/cpujan2021.html","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.oracle.com/security-alerts/cpuoct2021.html","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.tenable.com/security/tns-2020-11","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.tenable.com/security/tns-2021-09","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"https://www.tenable.com/security/tns-2021-10","tags":["Third Party Advisory"],"source":"openssl-security@openssl.org"},{"url":"http://www.openwall.com/lists/oss-security/2021/09/14/2","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=2154ab83e14ede338d2ede9bbe5cdfce5d5a6c9e","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=f960d81215ebf3f65e03d4d5d857fb9b666d6920","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44676","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.apache.org/thread.html/r63c6f2dd363d9b514d0a4bcf624580616a679898cc14c109a49b750c%40%3Cdev.tomcat.apache.org%3E","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.apache.org/thread.html/rbb769f771711fb274e0a4acb1b5911c8aab544a6ac5e8c12d40c5143%40%3Ccommits.pulsar.apache.org%3E","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2020/12/msg00020.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2020/12/msg00021.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DGSI34Y5LQ5RYXN4M2I5ZQT65LFVDOUU/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PWPSSZNZOBJU2YR6Z4TGHXKYW3YP5QG7/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-20:33.openssl.asc","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202012-13","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20201218-0005/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210513-0002/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20240621-0006/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2020/dsa-4807","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.openssl.org/news/secadv/20201208.txt","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpuApr2021.html","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpujan2021.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpuoct2021.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2020-11","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2021-09","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2021-10","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2020-1971","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}