ubuntu-cve-2025-4877
Vulnerability from osv_ubuntu
Published
2025-06-25 00:00
Modified
2026-04-22 07:53
Summary
Details

There's a vulnerability in the libssh package where when a libssh consumer passes in an unexpectedly large input buffer to ssh_get_fingerprint_hash() function. In such cases the bin_to_base64() function can experience an integer overflow leading to a memory under allocation, when that happens it's possible that the program perform out of bounds write leading to a heap corruption. This issue affects only 32-bits builds of libssh.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.6.3-4.3ubuntu0.6+esm2"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.6.3-4.3ubuntu0.6+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.6.3-4.3ubuntu0.6+esm2?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.6.3-4.3ubuntu0.6+esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.6.3-3ubuntu3",
        "0.6.3-4.1",
        "0.6.3-4.2",
        "0.6.3-4.2ubuntu1",
        "0.6.3-4.3",
        "0.6.3-4.3ubuntu0.1",
        "0.6.3-4.3ubuntu0.2",
        "0.6.3-4.3ubuntu0.5",
        "0.6.3-4.3ubuntu0.6",
        "0.6.3-4.3ubuntu0.6+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.8.0~20170825.94fa1e38-1ubuntu0.7+esm4"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.8.0~20170825.94fa1e38-1ubuntu0.7+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.8.0~20170825.94fa1e38-1ubuntu0.7+esm4?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.8.0~20170825.94fa1e38-1ubuntu0.7+esm4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.7.5-1",
        "0.8.0~20170825.94fa1e38-1",
        "0.8.0~20170825.94fa1e38-1build1",
        "0.8.0~20170825.94fa1e38-1ubuntu0.1",
        "0.8.0~20170825.94fa1e38-1ubuntu0.2",
        "0.8.0~20170825.94fa1e38-1ubuntu0.5",
        "0.8.0~20170825.94fa1e38-1ubuntu0.6",
        "0.8.0~20170825.94fa1e38-1ubuntu0.7",
        "0.8.0~20170825.94fa1e38-1ubuntu0.7+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.9.3-2ubuntu2.5+esm1"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.9.3-2ubuntu2.5+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.9.3-2ubuntu2.5+esm1?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.9.3-2ubuntu2.5+esm1"
            }
          ],
          "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",
        "0.9.3-2ubuntu2.3",
        "0.9.3-2ubuntu2.4",
        "0.9.3-2ubuntu2.5"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.9.6-2ubuntu0.22.04.4"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.9.6-2ubuntu0.22.04.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.9.6-2ubuntu0.22.04.4?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.9.6-2ubuntu0.22.04.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.9.6-1",
        "0.9.6-1build1",
        "0.9.6-2",
        "0.9.6-2build1",
        "0.9.6-2ubuntu0.22.04.1",
        "0.9.6-2ubuntu0.22.04.2",
        "0.9.6-2ubuntu0.22.04.3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssh-4",
            "binary_version": "0.10.6-2ubuntu0.1"
          },
          {
            "binary_name": "libssh-gcrypt-4",
            "binary_version": "0.10.6-2ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libssh",
        "purl": "pkg:deb/ubuntu/libssh@0.10.6-2ubuntu0.1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.10.6-2ubuntu0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.10.5-3ubuntu1",
        "0.10.5-3ubuntu2",
        "0.10.6-2",
        "0.10.6-2build1",
        "0.10.6-2build2"
      ]
    }
  ],
  "aliases": [],
  "details": "There\u0027s a vulnerability in the libssh package where when a libssh consumer passes in an unexpectedly large input buffer to ssh_get_fingerprint_hash() function. In such cases the bin_to_base64() function can experience an integer overflow leading to a memory under allocation, when that happens it\u0027s possible that the program perform out of bounds write leading to a heap corruption. This issue affects only 32-bits builds of libssh.",
  "id": "UBUNTU-CVE-2025-4877",
  "modified": "2026-04-22T07:53:18Z",
  "published": "2025-06-25T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2025-4877"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-4877"
    },
    {
      "type": "REPORT",
      "url": "https://www.libssh.org/security/advisories/CVE-2025-4877.txt"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-7619-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-7696-1"
    }
  ],
  "related": [
    "USN-7619-1",
    "USN-7696-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2025-4877"
  ]
}



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