Skip to content
CVE PROGRAM SOURCE RECORD5.7 Medium

CVE-2026-107737

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

sumatrapdfreader sumatrapdf

  • <= 3.6.1affected

References