{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23951", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-01-19T14:49:06.312Z", "datePublished": "2026-01-22T00:17:10.159Z", "dateUpdated": "2026-01-22T00:17:10.159Z"}, "containers": {"cna": {"title": "SumatraPDF's Integer Underflow in PalmDbReader Leads to Crash", "problemTypes": [{"descriptions": [{"cweId": "CWE-125", "lang": "en", "description": "CWE-125: Out-of-bounds Read", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-191", "lang": "en", "description": "CWE-191: Integer Underflow (Wrap or Wraparound)", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-hj4w-c5x8-p2hv", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-hj4w-c5x8-p2hv"}, {"name": "https://github.com/sumatrapdfreader/sumatrapdf/blob/master/src/PalmDbReader.cpp", "tags": ["x_refsource_MISC"], "url": "https://github.com/sumatrapdfreader/sumatrapdf/blob/master/src/PalmDbReader.cpp"}], "affected": [{"vendor": "sumatrapdfreader", "product": "sumatrapdf", "versions": [{"version": "<= 3.5.2rel", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-01-22T00:17:10.159Z"}, "descriptions": [{"lang": "en", "value": "SumatraPDF is a multi-format reader for Windows. All versions contain an off-by-one error in the validation code that only triggers with exactly 2 records, causing an integer underflow in the size calculation. This bug exists in PalmDbReader::GetRecord when opening a crafted Mobi file, resulting in an out-of-bounds heap read that crashes the app. There are no published fixes at the time of publication."}], "source": {"advisory": "GHSA-hj4w-c5x8-p2hv", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "SumatraPDF is a multi-format reader for Windows. All versions contain an off-by-one error in the validation code that only triggers with exactly 2 records, causing an integer underflow in the size calculation. This bug exists in PalmDbReader::GetRecord when opening a crafted Mobi file, resulting in an out-of-bounds heap read that crashes the app. There are no published fixes at the time of publication."}], "id": "CVE-2026-23951", "lastModified": "2026-01-22T01:15:52.633", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-01-22T01:15:52.633", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/sumatrapdfreader/sumatrapdf/blob/master/src/PalmDbReader.cpp"}, {"source": "security-advisories@github.com", "url": "https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-hj4w-c5x8-p2hv"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-125"}, {"lang": "en", "value": "CWE-191"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}