CVE-2026-107730 SumatraPDF: Signed integer overflow in the LIT header parsing causes invalid-pointer read
A signed integer overflow in SumatraPDF's LIT header parsing causes an invalid pointer read, leading to application termination.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-107730?
CVE-2026-107730 is a medium-severity vulnerability in sumatrapdfreader sumatrapdf, published on 8 Oct 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-190
Which versions are affected by CVE-2026-107730?
How do I fix CVE-2026-107730?
No fix has been published for CVE-2026-107730 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-107730 being exploited?
There is no known exploitation of CVE-2026-107730 in the wild and no public exploit code.
Sources
Also known as GHSA-vfpj-qhvj-92wg.