UBUNTU-CVE-2026-18938 (CVE-2026-18938)

Vulnerability from osv_ubuntu – Published: 2026-08-07 09:16 – Updated: 2026-08-31 14:18 – Source website
VLAI
Details

A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC channel, could exploit an integer overflow vulnerability. By sending specially crafted messages, the attacker can cause the system to miscalculate memory allocation for nested attributes. This leads to a memory corruption issue, specifically a heap out-of-bounds write, which can crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). This vulnerability is only exploitable on 32 bit systems.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libp11-kit0",
            "binary_version": "0.23.9-2ubuntu0.1+esm1"
          },
          {
            "binary_name": "p11-kit",
            "binary_version": "0.23.9-2ubuntu0.1+esm1"
          },
          {
            "binary_name": "p11-kit-modules",
            "binary_version": "0.23.9-2ubuntu0.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "p11-kit",
        "purl": "pkg:deb/ubuntu/p11-kit@0.23.9-2ubuntu0.1+esm1?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.9-2ubuntu0.1+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.23.7-3",
        "0.23.9-2",
        "0.23.9-2ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libp11-kit0",
            "binary_version": "0.23.20-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "p11-kit",
            "binary_version": "0.23.20-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "p11-kit-modules",
            "binary_version": "0.23.20-1ubuntu0.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "p11-kit",
        "purl": "pkg:deb/ubuntu/p11-kit@0.23.20-1ubuntu0.1+esm1?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.20-1ubuntu0.1+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.23.17-2",
        "0.23.18.1-2",
        "0.23.19-2",
        "0.23.20-1",
        "0.23.20-1build1",
        "0.23.20-1ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libp11-kit0",
            "binary_version": "0.24.0-6ubuntu0.1"
          },
          {
            "binary_name": "p11-kit",
            "binary_version": "0.24.0-6ubuntu0.1"
          },
          {
            "binary_name": "p11-kit-modules",
            "binary_version": "0.24.0-6ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "p11-kit",
        "purl": "pkg:deb/ubuntu/p11-kit@0.24.0-6ubuntu0.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.24.0-6ubuntu0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.23.22-1build1",
        "0.24.0-5",
        "0.24.0-6",
        "0.24.0-6build1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libp11-kit0",
            "binary_version": "0.25.3-4ubuntu2.2"
          },
          {
            "binary_name": "p11-kit",
            "binary_version": "0.25.3-4ubuntu2.2"
          },
          {
            "binary_name": "p11-kit-modules",
            "binary_version": "0.25.3-4ubuntu2.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "p11-kit",
        "purl": "pkg:deb/ubuntu/p11-kit@0.25.3-4ubuntu2.2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.25.3-4ubuntu2.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.25.0-4ubuntu1",
        "0.25.3-2ubuntu2",
        "0.25.3-4ubuntu1",
        "0.25.3-4ubuntu2",
        "0.25.3-4ubuntu2.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libp11-kit0",
            "binary_version": "0.26.2-2"
          },
          {
            "binary_name": "p11-kit",
            "binary_version": "0.26.2-2"
          },
          {
            "binary_name": "p11-kit-modules",
            "binary_version": "0.26.2-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "p11-kit",
        "purl": "pkg:deb/ubuntu/p11-kit@0.26.2-2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.25.5-3ubuntu1",
        "0.25.9-2",
        "0.25.10-1",
        "0.25.10-1ubuntu1",
        "0.26.2-2"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC channel, could exploit an integer overflow vulnerability. By sending specially crafted messages, the attacker can cause the system to miscalculate memory allocation for nested attributes. This leads to a memory corruption issue, specifically a heap out-of-bounds write, which can crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). This vulnerability is only exploitable on 32 bit systems.",
  "id": "UBUNTU-CVE-2026-18938",
  "modified": "2026-08-31T14:18:43Z",
  "published": "2026-08-07T09:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-18938"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-18938"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-18938"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8687-1"
    }
  ],
  "related": [
    "USN-8687-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-18938"
  ]
}



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