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ubuntu-cve-2023-2283
Vulnerability from osv_ubuntu
Published
2023-05-09 00:00
Modified
2026-04-22 07:44
Summary
Details

A vulnerability was found in libssh, where the authentication check of the connecting client can be bypassed in thepki_verify_data_signature function in memory allocation problems. This issue may happen if there is insufficient memory or the memory usage is limited. The problem is caused by the return value rc, which is initialized to SSH_ERROR and later rewritten to save the return value of the function call pki_key_check_hash_compatible. The value of the variable is not changed between this point and the cryptographic verification. Therefore any error between them calls goto error returning SSH_OK.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.9.3-2ubuntu2.3"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.9.3-2ubuntu2.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.9.3-2ubuntu2.3?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.9.3-2ubuntu2.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.9.0-1ubuntu1",
        "0.9.0-1ubuntu4",
        "0.9.0-1ubuntu5",
        "0.9.3-2ubuntu1",
        "0.9.3-2ubuntu2",
        "0.9.3-2ubuntu2.1",
        "0.9.3-2ubuntu2.2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.9.6-2ubuntu0.22.04.1"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.9.6-2ubuntu0.22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.9.6-2ubuntu0.22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.9.6-2ubuntu0.22.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.9.6-1",
        "0.9.6-1build1",
        "0.9.6-2",
        "0.9.6-2build1"
      ]
    }
  ],
  "aliases": [],
  "details": "A vulnerability was found in libssh, where the authentication check of the connecting client can be bypassed in the`pki_verify_data_signature` function in memory allocation problems. This issue may happen if there is insufficient memory or the memory usage is limited. The problem is caused by the return value `rc,` which is initialized to SSH_ERROR and later rewritten to save the return value of the function call `pki_key_check_hash_compatible.` The value of the variable is not changed between this point and the cryptographic verification. Therefore any error between them calls `goto error` returning SSH_OK.",
  "id": "UBUNTU-CVE-2023-2283",
  "modified": "2026-04-22T07:44:59Z",
  "published": "2023-05-09T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2023-2283"
    },
    {
      "type": "REPORT",
      "url": "https://www.libssh.org/security/advisories/CVE-2023-2283.txt"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6138-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-2283"
    }
  ],
  "related": [
    "USN-6138-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2023-2283"
  ]
}



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