UBUNTU-CVE-2026-4541 (CVE-2026-4541)

Vulnerability from osv_ubuntu – Published: 2026-03-22 09:15 – Updated: 2026-05-20 15:24 – Source website
VLAI
Details

A flaw has been found in janmojzis tinyssh up to 20250501. Impacted is an unknown function of the file tinyssh/crypto_sign_ed25519_tinyssh.c of the component Ed25519 Signature Handler. This manipulation causes improper verification of cryptographic signature. The attack is restricted to local execution. The attack's complexity is rated as high. The exploitability is considered difficult. The exploit has been published and may be used. Upgrading to version 20260301 is recommended to address this issue. Patch name: 9c87269607e0d7d20174df742accc49c042cff17. Upgrading the affected component is recommended.

Severity
2.5 (Low)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
1.1 (Low)
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tinysshd",
            "binary_version": "20180201-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "tinyssh",
        "purl": "pkg:deb/ubuntu/tinyssh@20180201-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "20180101-1",
        "20180201-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tinysshd",
            "binary_version": "20190101-1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "tinyssh",
        "purl": "pkg:deb/ubuntu/tinyssh@20190101-1build1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "20190101-1build1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tinysshd",
            "binary_version": "20190101-1ubuntu1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "tinyssh",
        "purl": "pkg:deb/ubuntu/tinyssh@20190101-1ubuntu1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "20190101-1build1",
        "20190101-1ubuntu1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tinysshd",
            "binary_version": "20240101-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "tinyssh",
        "purl": "pkg:deb/ubuntu/tinyssh@20240101-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "20230101-2",
        "20230101-3",
        "20230101-4",
        "20240101-1",
        "20240101-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tinysshd",
            "binary_version": "20250501-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "tinyssh",
        "purl": "pkg:deb/ubuntu/tinyssh@20250501-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "20250201-1",
        "20250501-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tinysshd",
            "binary_version": "20250501-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "tinyssh",
        "purl": "pkg:deb/ubuntu/tinyssh@20250501-2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "20250501-1",
        "20250501-2"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw has been found in janmojzis tinyssh up to 20250501. Impacted is an unknown function of the file tinyssh/crypto_sign_ed25519_tinyssh.c of the component Ed25519 Signature Handler. This manipulation causes improper verification of cryptographic signature. The attack is restricted to local execution. The attack\u0027s complexity is rated as high. The exploitability is considered difficult. The exploit has been published and may be used. Upgrading to version 20260301 is recommended to address this issue. Patch name: 9c87269607e0d7d20174df742accc49c042cff17. Upgrading the affected component is recommended.",
  "id": "UBUNTU-CVE-2026-4541",
  "modified": "2026-05-20T15:24:30Z",
  "published": "2026-03-22T09:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-4541"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-4541"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/janmojzis/tinyssh/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/janmojzis/tinyssh/commit/9c87269607e0d7d20174df742accc49c042cff17"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/janmojzis/tinyssh/issues/101"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/janmojzis/tinyssh/issues/101#issue-3983586116"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/janmojzis/tinyssh/pull/102"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/janmojzis/tinyssh/releases/tag/20260301"
    },
    {
      "type": "REPORT",
      "url": "https://vuldb.com/?ctiid.352358"
    },
    {
      "type": "REPORT",
      "url": "https://vuldb.com/?id.352358"
    },
    {
      "type": "REPORT",
      "url": "https://vuldb.com/?submit.774687"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-4541"
  ]
}



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