CVE-2026-1591: Stored XSS via Attachments Feature in https://pdfonline.foxit.com/

Severity: medium (CVSS 5.4 v3.1)
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: 2026-02-03 · updated 2026-06-17
Weakness: CWE-79

Description

Foxit PDF Editor Cloud (pdfonline) contains a stored cross-site scripting vulnerability in the file upload feature. A malicious username is embedded into the upload file list without proper escaping, allowing arbitrary JavaScript execution when the list is displayed. This issue affects pdfonline.foxit.com: before 2026‑02‑03.

Affected products

Foxit Pdf Editor Cloud: before 2026-02-03 — fixed in 2026-02-03

How to fix

Upgrade to a fixed version: Foxit Pdf Editor Cloud 2026-02-03. Check the vendor advisory for mitigations.

References

https://www.foxit.com/support/security-bulletins.html

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