CVE-2026-107737

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/sumatrapdfreader/sumatrapdf/commit/596c7e26e983549a77a3a38cae1147ab73792929
https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-8p34-f32f-7rmq
https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-8p34-f32f-7rmq

Configurations

No configuration.

History

13 Oct 2026, 17:17

Type	Values Removed	Values Added
References	~~() https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-8p34-f32f-7rmq -~~	() https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-8p34-f32f-7rmq -

08 Oct 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 23:16

Updated : 2026-10-13 17:17

NVD link : CVE-2026-107737

Mitre link : CVE-2026-107737

CVE.ORG link : CVE-2026-107737

JSON object : View

Products Affected

No product.

CWE

CWE-129

Improper Validation of Array Index

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