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TI-2020-10771 Aliases CVE-2020-13777GHSA-cv49-m792-xmjv

GnuTLS 3.6.x before 3.6.14 uses incorrect cryptography for encrypting a session ticket (a…

Priority MEDIUM 52CWE-327Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-327.

Summary

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.

Why it matters now

EPSS 0.22455 97th percentileScored 2026-11-07
Fix Fixed Red Hat: 3 advisories

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:*3.6.0 to before 3.6.14VulnerableGNU
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*31VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*32VulnerableFedoraproject
cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*19.10VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*20.04VulnerableCanonical
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
  • cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:* Versions 3.6.0 to before 3.6.14 Vulnerable ·GNU
  • cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
  • cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:* Versions 19.10 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* Versions 20.04 Vulnerable ·Canonical
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian

Remediation

Red Hat 3 advisories

  • RHSA-2020:2637 Released 2020-06-22 · Red Hat rating Important
    gnutls security update
    • Red Hat Enterprise Linux AppStream (v. 8) gnutls-c++-3.6.8-11.el8_2, gnutls-dane-3.6.8-11.el8_2, gnutls-devel-3.6.8-11.el8_2 +1
    • Red Hat Enterprise Linux BaseOS (v. 8) gnutls-3.6.8-11.el8_2
  • RHSA-2020:2638 Released 2020-06-22 · Red Hat rating Important
    gnutls security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) gnutls-c++-3.6.8-9.el8_1, gnutls-dane-3.6.8-9.el8_1, gnutls-devel-3.6.8-9.el8_1 +1
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.1) gnutls-3.6.8-9.el8_1
  • RHSA-2020:2639 Released 2020-06-22 · Red Hat rating Important
    gnutls security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.0) gnutls-c++-3.6.5-3.el8_0, gnutls-dane-3.6.5-3.el8_0, gnutls-devel-3.6.5-3.el8_0 +1
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.0) gnutls-3.6.5-3.el8_0

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2020:2637
Red Hat Enterprise Linux AppStream E4S (v. 8.0)Fixed RHSA-2020:2639
Red Hat Enterprise Linux AppStream EUS (v. 8.1)Fixed RHSA-2020:2638
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2020:2637
Red Hat Enterprise Linux BaseOS E4S (v. 8.0)Fixed RHSA-2020:2639
Red Hat Enterprise Linux BaseOS EUS (v. 8.1)Fixed RHSA-2020:2638
Not affected: 3 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-13777
  2. 2026-10-03 Alias added: GHSA-cv49-m792-xmjv

References

Advisory 10

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences