CVE-2026-91817: Foxit PDF Editor

Medium severity, CVSS 6.1. EPSS: 0.1% chance of exploitation in the next 30 days.

A heap-based out-of-bounds read vulnerability exists in Foxit PDF Editor/Reader’s handling of wide strings in embedded PDF JavaScript. Insufficient validation of string-deletion ranges can cause an integer underflow, resulting in an out-of-bounds read and application crash.

Affected products

• Foxit PDF Editor: up to and including 13.2.5.63482; from 14.0.0.33046, up to and including 14.0.7.33751; from 2023.1.0.15510, up to and including 2023.3.0.23028; from 2024.1.0.23997, up to and including 2024.4.1.27687; from 2025.1.0.27937, up to and including 2025.3.0.35737; from 2026.1.0.36452, up to and including 2026.2.0.39747
• Foxit PDF Reader: up to and including 2026.2.0.39747

Published 2026-09-23. Last modified 2026-10-01.