UBUNTU-CVE-2026-56116 (CVE-2026-56116)

Vulnerability from osv_ubuntu – Published: 2026-06-23 17:17 – Updated: 2026-09-24 21:35 – Source website
VLAI
Details

dhcpcd through 10.3.2, fixed in commit 708b4a5, contains a memory leak vulnerability in the IPv6 Router Advertisement route information handling that allows an unauthenticated same-link attacker to cause denial of service by sending crafted Router Advertisements. Attackers can repeatedly send Router Advertisements containing Route Information options with a lifetime of zero, triggering unfreed allocations in routeinfo_findalloc() that cause linear memory exhaustion and eventual daemon crash.

Severity
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.1 (High)
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dhcpcd",
            "binary_version": "1:10.2.4-4"
          },
          {
            "binary_name": "dhcpcd-base",
            "binary_version": "1:10.2.4-4"
          },
          {
            "binary_name": "dhcpcd5",
            "binary_version": "1:10.2.4-4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "dhcpcd",
        "purl": "pkg:deb/ubuntu/dhcpcd@1:10.2.4-4?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:10.1.0-8",
        "1:10.1.0-10",
        "1:10.1.0-11",
        "1:10.1.0-12",
        "1:10.2.4-3",
        "1:10.2.4-4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dhcpcd",
            "binary_version": "1:10.3.0-7"
          },
          {
            "binary_name": "dhcpcd-base",
            "binary_version": "1:10.3.0-7"
          },
          {
            "binary_name": "dhcpcd5",
            "binary_version": "1:10.3.0-7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "dhcpcd",
        "purl": "pkg:deb/ubuntu/dhcpcd@1:10.3.0-7?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:10.2.4-4",
        "1:10.3.0-2",
        "1:10.3.0-3",
        "1:10.3.0-7"
      ]
    }
  ],
  "aliases": [],
  "details": "dhcpcd through 10.3.2, fixed in commit 708b4a5, contains a memory leak vulnerability in the IPv6 Router Advertisement route information handling that allows an unauthenticated same-link attacker to cause denial of service by sending crafted Router Advertisements. Attackers can repeatedly send Router Advertisements containing Route Information options with a lifetime of zero, triggering unfreed allocations in routeinfo_findalloc() that cause linear memory exhaustion and eventual daemon crash.",
  "id": "UBUNTU-CVE-2026-56116",
  "modified": "2026-09-24T21:35:23Z",
  "published": "2026-06-23T17:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-56116"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-56116"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:A/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"
    }
  ],
  "upstream": [
    "CVE-2026-56116"
  ]
}



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