CVE-2020-13777
GnuTLS 3.6.x before 3.6.14 uses incorrect cryptography for encrypting a session ticket (a loss of confidentiality in TLS 1.2, and an authentication bypass in TLS 1.3).
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 22.3%, higher than 98% of all known CVEs. Patch or mitigate before the next change window.
Description
GnuTLS 3.6.x before 3.6.14 uses incorrect cryptography for encrypting a session ticket (a loss of confidentiality in TLS 1.2, and an authentication bypass in TLS 1.3). The earliest affected version is 3.6.4 (2018-09-24) because of an error in a 2018-09-18 commit. Until the first key rotation, the TLS server always uses wrong data in place of an encryption key derived from an application.
- CVSS 3.1
- 7.4 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 22.28% probability · 98th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-327
- Affected
- gnu/gnutls · fedoraproject/fedora · canonical/ubuntu linux · debian/debian linux
- Source
- cve@mitre.org
EPSS moved from 22.3% on 24 September 2026 to 22.3% on 3 November 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00015.htmlBroken Link
- https://gnutls.org/security-new.html#GNUTLS-SA-2020-06-03Vendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6C4DHUKV6M6SJ5CV6KVHZNHNF7HCUE5P/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6RTXZOXC4MHTFE2HKY6IAZMF2WHD2WMV/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RRQBFK3UZ7SV76IYDTS4PS6ABS2DSJHK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VMB3UGI5H5RCFRU6OGRPMNUCNLJGEN7Y/
- https://security.gentoo.org/glsa/202006-01Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200619-0004/Third Party Advisory
- https://usn.ubuntu.com/4384-1/Third Party Advisory
- https://www.debian.org/security/2020/dsa-4697Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00015.htmlBroken Link
- https://gnutls.org/security-new.html#GNUTLS-SA-2020-06-03Vendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6C4DHUKV6M6SJ5CV6KVHZNHNF7HCUE5P/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6RTXZOXC4MHTFE2HKY6IAZMF2WHD2WMV/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RRQBFK3UZ7SV76IYDTS4PS6ABS2DSJHK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VMB3UGI5H5RCFRU6OGRPMNUCNLJGEN7Y/
- https://security.gentoo.org/glsa/202006-01Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200619-0004/Third Party Advisory
- https://usn.ubuntu.com/4384-1/Third Party Advisory
- https://www.debian.org/security/2020/dsa-4697Third Party Advisory
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.