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UBUNTU-CVE-2018-15919 (CVE-2018-15919)

Vulnerability from osv_ubuntu – Published: 2018-08-28 08:29 – Updated: 2026-09-16 11:07 – Source website
VLAI
Details

Remotely observable behaviour in auth-gss2.c in OpenSSH through 7.8 could be used by remote attackers to detect existence of users on a target system when GSS2 is in use. NOTE: the discoverer states 'We understand that the OpenSSH developers do not want to treat such a username enumeration (or "oracle") as a vulnerability.'

Severity
5.3 (Medium)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:6.6p1-2ubuntu2.13+esm3"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:6.6p1-2ubuntu2.13+esm3"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:6.6p1-2ubuntu2.13+esm3"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:6.6p1-2ubuntu2.13+esm3"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:6.6p1-2ubuntu2.13+esm3"
          },
          {
            "binary_name": "ssh-krb5",
            "binary_version": "1:6.6p1-2ubuntu2.13+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:6.6p1-2ubuntu2.13+esm3?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:6.2p2-6",
        "1:6.2p2-6ubuntu1",
        "1:6.4p1-1",
        "1:6.4p1-2",
        "1:6.5p1-1",
        "1:6.5p1-2",
        "1:6.5p1-3",
        "1:6.5p1-4",
        "1:6.5p1-6",
        "1:6.6p1-1",
        "1:6.6p1-2",
        "1:6.6p1-2ubuntu1",
        "1:6.6p1-2ubuntu2",
        "1:6.6p1-2ubuntu2.2",
        "1:6.6p1-2ubuntu2.3",
        "1:6.6p1-2ubuntu2.4",
        "1:6.6p1-2ubuntu2.6",
        "1:6.6p1-2ubuntu2.7",
        "1:6.6p1-2ubuntu2.8",
        "1:6.6p1-2ubuntu2.10",
        "1:6.6p1-2ubuntu2.11",
        "1:6.6p1-2ubuntu2.12",
        "1:6.6p1-2ubuntu2.13",
        "1:6.6p1-2ubuntu2.13+esm1",
        "1:6.6p1-2ubuntu2.13+esm2",
        "1:6.6p1-2ubuntu2.13+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          },
          {
            "binary_name": "openssh-client-ssh1",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          },
          {
            "binary_name": "ssh-krb5",
            "binary_version": "1:7.2p2-4ubuntu2.10+esm9"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:7.2p2-4ubuntu2.10+esm9?arch=source\u0026distro=esm-infra-legacy/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:6.9p1-2",
        "1:6.9p1-3",
        "1:7.1p1-1",
        "1:7.1p1-3",
        "1:7.1p1-4",
        "1:7.1p1-6",
        "1:7.1p2-1",
        "1:7.1p2-2",
        "1:7.2p1-1",
        "1:7.2p2-1",
        "1:7.2p2-2",
        "1:7.2p2-3",
        "1:7.2p2-4",
        "1:7.2p2-4ubuntu1",
        "1:7.2p2-4ubuntu2.1",
        "1:7.2p2-4ubuntu2.2",
        "1:7.2p2-4ubuntu2.4",
        "1:7.2p2-4ubuntu2.5",
        "1:7.2p2-4ubuntu2.6",
        "1:7.2p2-4ubuntu2.7",
        "1:7.2p2-4ubuntu2.8",
        "1:7.2p2-4ubuntu2.10",
        "1:7.2p2-4ubuntu2.10+esm1",
        "1:7.2p2-4ubuntu2.10+esm2",
        "1:7.2p2-4ubuntu2.10+esm3",
        "1:7.2p2-4ubuntu2.10+esm4",
        "1:7.2p2-4ubuntu2.10+esm5",
        "1:7.2p2-4ubuntu2.10+esm6",
        "1:7.2p2-4ubuntu2.10+esm7",
        "1:7.2p2-4ubuntu2.10+esm8",
        "1:7.2p2-4ubuntu2.10+esm9"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:7.6p1-4ubuntu0.7+esm5"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:7.6p1-4ubuntu0.7+esm5"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:7.6p1-4ubuntu0.7+esm5"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:7.6p1-4ubuntu0.7+esm5"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:7.6p1-4ubuntu0.7+esm5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:7.6p1-4ubuntu0.7+esm5?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:7.5p1-10",
        "1:7.6p1-4",
        "1:7.6p1-4ubuntu0.1",
        "1:7.6p1-4ubuntu0.2",
        "1:7.6p1-4ubuntu0.3",
        "1:7.6p1-4ubuntu0.5",
        "1:7.6p1-4ubuntu0.6",
        "1:7.6p1-4ubuntu0.7",
        "1:7.6p1-4ubuntu0.7+esm1",
        "1:7.6p1-4ubuntu0.7+esm2",
        "1:7.6p1-4ubuntu0.7+esm3",
        "1:7.6p1-4ubuntu0.7+esm4",
        "1:7.6p1-4ubuntu0.7+esm5"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client-ssh1",
            "binary_version": "1:7.5p1-10"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "openssh-ssh1",
        "purl": "pkg:deb/ubuntu/openssh-ssh1@1:7.5p1-10?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:7.5p1-8",
        "1:7.5p1-9",
        "1:7.5p1-9build1",
        "1:7.5p1-10"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:8.2p1-4ubuntu0.13+esm2"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:8.2p1-4ubuntu0.13+esm2"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:8.2p1-4ubuntu0.13+esm2"
          },
          {
            "binary_name": "openssh-tests",
            "binary_version": "1:8.2p1-4ubuntu0.13+esm2"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:8.2p1-4ubuntu0.13+esm2"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:8.2p1-4ubuntu0.13+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:8.2p1-4ubuntu0.13+esm2?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:8.0p1-6build1",
        "1:8.1p1-1",
        "1:8.1p1-5",
        "1:8.2p1-4",
        "1:8.2p1-4ubuntu0.1",
        "1:8.2p1-4ubuntu0.2",
        "1:8.2p1-4ubuntu0.3",
        "1:8.2p1-4ubuntu0.4",
        "1:8.2p1-4ubuntu0.5",
        "1:8.2p1-4ubuntu0.7",
        "1:8.2p1-4ubuntu0.8",
        "1:8.2p1-4ubuntu0.9",
        "1:8.2p1-4ubuntu0.10",
        "1:8.2p1-4ubuntu0.11",
        "1:8.2p1-4ubuntu0.12",
        "1:8.2p1-4ubuntu0.13",
        "1:8.2p1-4ubuntu0.13+esm1",
        "1:8.2p1-4ubuntu0.13+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client-ssh1",
            "binary_version": "1:7.5p1-11build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "openssh-ssh1",
        "purl": "pkg:deb/ubuntu/openssh-ssh1@1:7.5p1-11build1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:7.5p1-11build1"
      ]
    }
  ],
  "aliases": [],
  "details": "Remotely observable behaviour in auth-gss2.c in OpenSSH through 7.8 could be used by remote attackers to detect existence of users on a target system when GSS2 is in use. NOTE: the discoverer states \u0027We understand that the OpenSSH developers do not want to treat such a username enumeration (or \"oracle\") as a vulnerability.\u0027",
  "id": "UBUNTU-CVE-2018-15919",
  "modified": "2026-09-16T11:07:23Z",
  "published": "2018-08-28T08:29:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2018-15919"
    },
    {
      "type": "REPORT",
      "url": "http://www.openwall.com/lists/oss-security/2018/08/27/2"
    },
    {
      "type": "REPORT",
      "url": "http://seclists.org/oss-sec/2018/q3/180"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2018-15919"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2018-15919"
  ]
}



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Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.