{"id":"CVE-2026-107738","revision":"ff5cae8b1e02497191916751b9f18f48","records":[{"revision":"ff5cae8b1e02497191916751b9f18f48","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-107738","aliases":[],"title":"SumatraPDF: Untrusted binary record offset used without lower-bound validation","description":"SumatraPDF is a multi-format reader for Windows. In 3.6.1 and earlier, ChmFile::GetCharZ() narrows file-controlled unsigned string offsets from /#WINDOWS and /#IVB to signed integers without a lower-bound check. An offset that becomes negative can make the function read before the /#STRINGS buffer, causing deterministic application termination. No broader impact is claimed beyond the advisory-supported conditions. No fixed version is available as of this review.","state":0,"publishedAt":"2026-10-08T22:35:30.475+00:00","modifiedAt":"2026-10-14T01:36:13.121+00:00","affected":[{"ecosystem":"Vendor product","name":"sumatrapdf","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"sumatrapdfreader\",\n                    \"product\": \"sumatrapdf\",\n                    \"versions\": [\n                        {\n                            \"version\": \"<= 3.6.1\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"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","score":6.8,"severity":"MEDIUM"}],"references":["https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-33jg-vxm6-8mxx","https://github.com/sumatrapdfreader/sumatrapdf/commit/62254ed6d781ceb5cd16489bb423e7f591cd72c4"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-107738","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-107738","identifiers":["CVE-2026-107738"]},"retained":false,"historicalAffected":[]}],"coverage":[]}