{"id":"CVE-2020-11501","title":"GnuTLS 3.6.x before 3.6.13 uses incorrect cryptography for DTLS","summary":"GnuTLS 3.6.x before 3.6.13 uses incorrect cryptography for DTLS. The earliest affected version is 3.6.3 (2018-07-16) because of an error in a 2017-10-06 commit. The DTLS client always uses 32 '\\0' bytes instead of a random value, and thu…","severity":"high","cvss":7.4,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-330"],"vendor":"gnu","product":"gnutls","affected":["gnutls >= 3.6.3, < 3.6.13","ubuntu_linux = 19.10","debian_linux = 10.0","leap = 15.1","fedora = 31","fedora = 32"],"patched":["gnutls 3.6.13"],"published":"2020-04-03","updated":"2026-10-14","sourceUpdated":"2026-10-14T09:17:17.877","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2020-11501","references":[{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00015.html","label":"cve@mitre.org"},{"url":"https://gitlab.com/gnutls/gnutls/-/commit/5b595e8e52653f6c5726a4cdd8fddeb6e83804d2","label":"cve@mitre.org"},{"url":"https://gitlab.com/gnutls/gnutls/-/issues/960","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ILMOWPKMTZAIMK5F32TUMO34XCABUCFJ/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WDYY3R4F5CUTFAMXH2C5NKYFVDEJLTT7/","label":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/202004-06","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20200416-0002/","label":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4322-1/","label":"cve@mitre.org"},{"url":"https://www.debian.org/security/2020/dsa-4652","label":"cve@mitre.org"},{"url":"https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-03-31","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00015.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://gitlab.com/gnutls/gnutls/-/commit/5b595e8e52653f6c5726a4cdd8fddeb6e83804d2","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://gitlab.com/gnutls/gnutls/-/issues/960","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ILMOWPKMTZAIMK5F32TUMO34XCABUCFJ/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WDYY3R4F5CUTFAMXH2C5NKYFVDEJLTT7/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202004-06","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20200416-0002/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4322-1/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2020/dsa-4652","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-03-31","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.03388,"epssPercentile":0.88528,"ingestedAt":"2026-10-14T09:24:26.054Z","slug":"CVE-2020-11501","body":"## Overview\n\nGnuTLS 3.6.x before 3.6.13 uses incorrect cryptography for DTLS. The earliest affected version is 3.6.3 (2018-07-16) because of an error in a 2017-10-06 commit. The DTLS client always uses 32 '\\0' bytes instead of a random value, and thus contributes no randomness to a DTLS negotiation. This breaks the security guarantees of the DTLS protocol.\n\n## Affected\n\n- `gnutls >= 3.6.3, < 3.6.13`\n- `ubuntu_linux = 19.10`\n- `debian_linux = 10.0`\n- `leap = 15.1`\n- `fedora = 31`\n- `fedora = 32`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `gnutls 3.6.13`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":40.7,"likelihood":0.7,"exploitation":0,"ransomware":0},"changes":[]}