ubuntu-cve-2020-13777
Vulnerability from osv_ubuntu
Published
2020-06-04 07:15
Modified
2026-04-22 07:39
Summary
Details

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.

Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
N/A (UNKNOWN)
high
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "gnutls-bin",
            "binary_version": "3.6.13-2ubuntu1.1"
          },
          {
            "binary_name": "guile-gnutls",
            "binary_version": "3.6.13-2ubuntu1.1"
          },
          {
            "binary_name": "libgnutls-dane0",
            "binary_version": "3.6.13-2ubuntu1.1"
          },
          {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.6.13-2ubuntu1.1"
          },
          {
            "binary_name": "libgnutls30",
            "binary_version": "3.6.13-2ubuntu1.1"
          },
          {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.6.13-2ubuntu1.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "gnutls28",
        "purl": "pkg:deb/ubuntu/gnutls28@3.6.13-2ubuntu1.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.6.13-2ubuntu1.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6.9-5ubuntu1",
        "3.6.9-5ubuntu2",
        "3.6.10-5",
        "3.6.11.1-2",
        "3.6.11.1-2ubuntu2",
        "3.6.13-2ubuntu1"
      ]
    }
  ],
  "aliases": [],
  "details": "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.",
  "id": "UBUNTU-CVE-2020-13777",
  "modified": "2026-04-22T07:39:25Z",
  "published": "2020-06-04T07:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2020-13777"
    },
    {
      "type": "REPORT",
      "url": "https://gnutls.org/security-new.html#GNUTLS-SA-2020-06-03"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4384-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2020-13777"
    }
  ],
  "related": [
    "USN-4384-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "high",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2020-13777"
  ]
}



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