USN-8550-1 (UBUNTU-CVE-2026-9539)

Vulnerability from osv_ubuntu – Published: 2026-07-15 13:59 – Updated: 2026-07-15 13:59 – Source website
VLAI
Summary
libslirp vulnerability
Details

It was discovered that libslirp incorrectly handled TCP urgent data. A privileged attacker inside a guest VM could possibly use this issue to obtain sensitive information from the host process memory.

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-9539",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libslirp0",
            "binary_version": "4.6.1-1ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libslirp",
        "purl": "pkg:deb/ubuntu/libslirp@4.6.1-1ubuntu0.2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.6.1-1ubuntu0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.4.0-1build1",
        "4.6.1-1",
        "4.6.1-1build1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-9539",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libslirp0",
            "binary_version": "4.7.0-1ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libslirp",
        "purl": "pkg:deb/ubuntu/libslirp@4.7.0-1ubuntu3.1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.7.0-1ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.7.0-1ubuntu1",
        "4.7.0-1ubuntu2",
        "4.7.0-1ubuntu3"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-9539",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libslirp0",
            "binary_version": "4.9.1-1ubuntu1.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libslirp",
        "purl": "pkg:deb/ubuntu/libslirp@4.9.1-1ubuntu1.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.9.1-1ubuntu1.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.8.0-1ubuntu1",
        "4.9.1-1ubuntu1"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that libslirp incorrectly handled TCP urgent data. A\nprivileged attacker inside a guest VM could possibly use this issue to\nobtain sensitive information from the host process memory.",
  "id": "USN-8550-1",
  "modified": "2026-07-15T13:59:22Z",
  "published": "2026-07-15T13:59:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8550-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-9539"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "libslirp vulnerability",
  "upstream": [
    "UBUNTU-CVE-2026-9539"
  ]
}



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