CVE-2026-107730: Sumatrapdfreader Sumatrapdf

Medium severity, CVSS 5.5. EPSS: 0.1% chance of exploitation in the next 30 days.

SumatraPDF is a multi-format reader for Windows. In 3.7.0.22298, LitParseHeader() in src/LitDoc.cpp computes the attacker-controlled hdrLen + nPieces * 16 section offset using signed 32-bit arithmetic without validating the complete result. When the component values make that aggregate calculation overflow to a negative value, pointer construction reaches an invalid read in LitU32(), causing deterministic application termination. The supplied evidence does not demonstrate code execution, information disclosure, arbitrary read, or integrity impact. No fixed version is available as of this review.

Affected products

• Sumatrapdfreader Sumatrapdf: up to and including 3.7.0.22298

Published 2026-10-08. Last modified 2026-10-09.