Cross-site scripting in LibreChat - CVE-2025-66452
Published: April 27, 2026
Vulnerability identifier: #VU128111
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Green
CVE-ID: CVE-2025-66452
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: LibreChat
Affected software:
LibreChat
LibreChat
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary script in the victim's browser.
The vulnerability exists due to improper neutralization of input during web page generation in api request handling when reflecting invalid JSON payloads in HTTP responses. A remote attacker can send a specially crafted request containing HTML or JavaScript code to execute arbitrary script in the victim's browser.
How to mitigate CVE-2025-66452
Install security update from vendor's website.