USN-8722-1 (UBUNTU-CVE-2026-66032)

Vulnerability from osv_ubuntu – Published: 2026-09-03 12:37 – Updated: 2026-09-03 12:37 – Source website
VLAI
Summary
libssh2 vulnerabilities
Details

It was discovered that libssh2 incorrectly handled certain SFTP server responses. A remote attacker controlling an SSH server could use this issue to cause libssh2 to crash or possibly execute arbitrary code. (CVE-2026-66032)

It was discovered that libssh2 incorrectly handled AES-GCM cipher negotiation. A remote attacker controlling an SSH server could possibly use this issue to cause libssh2 to crash, resulting in a denial of service. (CVE-2026-66033)

It was discovered that libssh2 incorrectly handled Encrypt-then-MAC cipher negotiation. A remote attacker controlling an SSH server could use this issue to cause libssh2 to crash or possibly execute arbitrary code. (CVE-2026-66035)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-66032",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-66033",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-66035",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssh2-1t64",
            "binary_version": "1.11.0-4.1ubuntu0.24.04.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libssh2",
        "purl": "pkg:deb/ubuntu/libssh2@1.11.0-4.1ubuntu0.24.04.4?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.11.0-4.1ubuntu0.24.04.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.11.0-2",
        "1.11.0-3",
        "1.11.0-4",
        "1.11.0-4.1build1",
        "1.11.0-4.1build2",
        "1.11.0-4.1ubuntu0.24.04.1",
        "1.11.0-4.1ubuntu0.24.04.2",
        "1.11.0-4.1ubuntu0.24.04.3"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-66032",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-66033",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-66035",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssh2-1t64",
            "binary_version": "1.11.1-1ubuntu0.26.04.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libssh2",
        "purl": "pkg:deb/ubuntu/libssh2@1.11.1-1ubuntu0.26.04.4?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.11.1-1ubuntu0.26.04.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.11.1-1build1",
        "1.11.1-1build2",
        "1.11.1-1ubuntu0.26.04.1",
        "1.11.1-1ubuntu0.26.04.2",
        "1.11.1-1ubuntu0.26.04.3"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that libssh2 incorrectly handled certain SFTP server\nresponses. A remote attacker controlling an SSH server could use this issue\nto cause libssh2 to crash or possibly execute arbitrary code.\n(CVE-2026-66032)\n\nIt was discovered that libssh2 incorrectly handled AES-GCM cipher\nnegotiation. A remote attacker controlling an SSH server could possibly use\nthis issue to cause libssh2 to crash, resulting in a denial of service.\n(CVE-2026-66033)\n\nIt was discovered that libssh2 incorrectly handled Encrypt-then-MAC cipher\nnegotiation. A remote attacker controlling an SSH server could use this\nissue to cause libssh2 to crash or possibly execute arbitrary code.\n(CVE-2026-66035)",
  "id": "USN-8722-1",
  "modified": "2026-09-03T12:37:05Z",
  "published": "2026-09-03T12:37:05Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8722-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-66032"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-66033"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-66035"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "libssh2 vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2026-66032",
    "UBUNTU-CVE-2026-66033",
    "UBUNTU-CVE-2026-66035"
  ]
}



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