CVE-2026-40457: Reflected XSS in LMS

Severity: low (CVSS 2.1 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-18 · updated 2026-06-22
Weakness: CWE-79

Description

A Reflected Cross-Site Scripting (XSS) vulnerability exists in LMS (LAN Management System) before commit 9c5651b in the "dbrecover.php" and "netremap.php" modules where unsanitized GET parameters are directly embedded into HTML output. This allows an attacker to inject arbitrary JavaScript when an authenticated user clicks a crafted link, provided the required conditions (such as a network defined in the system) are met.

References

https://cert.pl/posts/2026/06/CVE-2026-40455
https://github.com/chilek/lms/commit/9c5651b39bfd086cc34fc9a78ddaa8c0815af114
https://lms.org.pl/

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