{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "3.6"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "24b9ce83383bbaa48b3efe00e4d30cccea126198"
            },
            {
              "fixed": "b9732699d403ccb41f1135e0bd7f425c475e7689"
            }
          ],
          "repo": "https://github.com/sumatrapdfreader/sumatrapdf",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-27p6-wrfp-pgm8"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26054.json"
  },
  "details": "SumatraPDF is a multi-format reader for Windows. Prior to 3.6, the MobiDoc::ParseHeader function in src/MobiDoc.cpp validates a record using kMobiHeaderMinLen but DecodeMobiDocHeader constructs a decoder sized for kMobiHeaderLen without receiving the actual remaining buffer length. A malformed MOBI file can use an attacker-controlled header length to bypass optional-field early returns and cause the decoder to read beyond a short heap buffer. Opening the crafted document can crash SumatraPDF. This issue is fixed in version 3.6.",
  "id": "CVE-2026-26054",
  "modified": "2026-09-30T03:30:15.025112226Z",
  "published": "2026-09-24T16:48:03.247Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/sumatrapdfreader/sumatrapdf/releases/tag/3.6rel"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26054.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-27p6-wrfp-pgm8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-26054"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/sumatrapdfreader/sumatrapdf/issues/5318"
    },
    {
      "type": "FIX",
      "url": "https://github.com/sumatrapdfreader/sumatrapdf/commit/24b9ce83383bbaa48b3efe00e4d30cccea126198"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "SumatraPDF: Heap out-of-bounds read in MOBI header parser."
}