{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "0"
                  },
                  {
                    "fixed": "6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              },
              {
                "range": [
                  {
                    "fixed": "6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"
            }
          ],
          "repo": "https://github.com/openbsd/src",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56099.json"
  },
  "details": "OpenBSD before commit 6a23123 (2026-06-18) contains an out-of-bounds read vulnerability in the mpls_do_error function within sys/netmpls/mpls_input.c that allows remote attackers to disclose kernel stack memory by sending crafted MPLS frames with 16 labels and no Bottom-of-Stack bit set.",
  "id": "CVE-2026-56099",
  "modified": "2026-10-21T02:30:26.263324722Z",
  "published": "2026-06-18T19:29:08.271Z",
  "references": [
    {
      "type": "WEB",
      "url": "http://seclists.org/fulldisclosure/2026/Jun/17"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/06/19/3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56099.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56099"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/openbsd-mpls-do-error-kernel-stack-memory-disclosure-via-mpls-input"
    },
    {
      "type": "FIX",
      "url": "https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/openbsd/src"
    },
    {
      "type": "EVIDENCE",
      "url": "https://pop.argus-systems.ai/advisory/adv-040.html"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "OpenBSD mpls_do_error Kernel Stack Memory Disclosure via MPLS Input"
}