high7.5Public exploit code
CVE-2026-25961
SumatraPDF is a multi-format reader for Windows.
Public exploit code
Working exploit or proof of concept code has been published for this vulnerability. Treat unpatched systems as at risk.
- SumatraPDF 3.5.2 - Remote Code Execution2026-04-30 · webapps · multiple
Impact
SumatraPDF is a multi-format reader for Windows. In 3.5.0 through 3.5.2, SumatraPDF's update mechanism disables TLS hostname verification (INTERNET_FLAG_IGNORE_CERT_CN_INVALID) and executes installers without signature checks. A network attacker with any valid TLS certificate (e.g., Let's Encrypt) can intercept the update check request, inject a malicious installer URL, and achieve arbitrary code execution.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Sumatrapdfreader | Sumatrapdf | from 3.5 through 3.5.2 |