{"id":"CVE-2026-107737","revision":"7e23a90357b843a7bc6aced91fc2efda","records":[{"revision":"7e23a90357b843a7bc6aced91fc2efda","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-107737","aliases":[],"title":"SumatraPDF CHM `its://` signed index causes an out-of-bounds object lookup","description":"SumatraPDF is a multi-format reader for Windows. In 3.6.1 and earlier, and in pre-release 3.7.0.20369 when WebView2 is absent or cannot initialize, ParseProtoUrl() accepts the signed host component of an its:// URL and FindHtmlWindowById() uses it directly as an index into gHtmlWindows. Opening a crafted CHM through the IE fallback backend with a negative or otherwise out-of-range window identifier can cause an out-of-bounds pointer read followed by an invalid object callback dereference and process termination. No fixed version is available as of this review.","state":0,"publishedAt":"2026-10-08T22:34:16.436+00:00","modifiedAt":"2026-10-13T16:28:11.204+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:P/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":5.7,"severity":"MEDIUM"}],"references":["https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-8p34-f32f-7rmq","https://github.com/sumatrapdfreader/sumatrapdf/commit/596c7e26e983549a77a3a38cae1147ab73792929"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-107737","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-107737","identifiers":["CVE-2026-107737"]},"retained":false,"historicalAffected":[]}],"coverage":[]}