What’s Vulnerable › Vulnerabilities

CVE-2026-107735: SumatraPDF: `sumatrapdfrestrict.ini` never revokes any permission (fail-open policy initialization)

• Severity: medium (CVSS 5.4 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-08 · updated 2026-10-09
• Weakness: CWE-636

Description

SumatraPDF is a multi-format reader for Windows. In 3.6.1 and earlier, InitializePolicies() starts the sumatrapdfrestrict.ini path with gPolicyRestrictions set to Perm::All and only ORs permission bits, so the INI file never revokes permissions. Deploying SumatraPDF with this INI file, including a malformed file or zero-valued permission settings, can silently bypass configured disk, network, printing, registry, clipboard, preference, and fullscreen restrictions. The -restrict command-line path works correctly and is not affected. No fixed version is available as of this review.

Affected products

• sumatrapdfreader sumatrapdf: through 3.6.1

References

• https://github.com/sumatrapdfreader/sumatrapdf/commit/f72948b59405d3ddba527789898050ef411d0bb8
• https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-crhm-w5qr-wjj4
• https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-crhm-w5qr-wjj4

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