Reflected XSS in Foxit eSign crafted URL parameters
CVE-2025-66523 is a reflected cross-site scripting vulnerability in Foxit eSign affecting na1.foxitesign.foxit.com before 2026-01-16. The issue arises because URL parameters are embedded directly into JavaScript code or HTML attributes without proper contextual output encoding or sanitization. An attacker can craft a malicious link containing script payloads in those parameters; when an authenticated user visits the link, the payload executes in the browser within the Foxit eSign application context.
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Impact, mitigation & remediation
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Impact
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Mitigation
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Remediation
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Exploits
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Affected products & vendors
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Recent activity
5 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A medium-severity set of reflected XSS vulnerabilities affecting the na1.foxitesign.foxit.com eSign domain.
A moderate-severity XSS vulnerability in Foxit eSign triggered by specially crafted links/URL parameters, where untrusted input is embedded into JavaScript/HTML attributes without adequate encoding, potentially enabling script execution and downstream impacts like privilege escalation and cross-domain data theft for authenticated users.
Moderate-severity cross-site scripting (XSS) vulnerability in Foxit eSign caused by improper handling/encoding of URL parameters in crafted links, allowing script injection in the context of authenticated users and potentially enabling cross-domain data theft and privilege escalation.
Moderate-severity XSS vulnerability in Foxit eSign caused by improper handling/encoding of URL parameters in crafted links, allowing script injection in the context of authenticated users and potentially enabling privilege escalation and cross-domain data theft.
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Every observed campaign linking this CVE to a named adversary.
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Cross-references every affected SKU, including bundled OEM variants.
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