CVE-2026-25961

HIGH

7.5

Description

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.

CVE Details

CVSS v3.1 Score7.5

SeverityHIGH

CVSS VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack VectorNETWORK

ComplexityHIGH

Privileges RequiredNONE

User InteractionREQUIRED

Published2/9/2026

Last Modified2/20/2026

Sourcenvd

Honeypot Sightings0

Affected Products

sumatrapdfreader:sumatrapdf

Weaknesses (CWE)

CWE-295CWE-494CWE-494

References

https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-xpm2-rr5m-x96q(security-advisories@github.com)

IOC Correlations

No correlations recorded

This product uses data from the NVD API but is not endorsed or certified by the NVD.