CVE-2026-100522

5.1 MEDIUM 0.2% exploit odds Fix listed XSS Browser & mail

What it is

Cotonti through 1.0.0 contains a reflected cross-site scripting vulnerability in message.php where the lng parameter is not properly escaped before output in the confirmation dialog. Unauthenticated attackers can craft malicious links with script payloads in the lng parameter to execute arbitrary JavaScript in victim browser sessions.

At a glance

Exploitability: Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.
Exploit odds: 0.2% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-09-26 01:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-09-28 18:17 UTC Last updatedMost recent change to the record

Details

Published: 2026-09-26 01:17 UTC
Last modified: 2026-09-28 18:17 UTC
Exploit probability: 0.2% · EPSS, next 30 days
Weakness: CWE-79 · Cross-site scripting
Record status: Deferred

Attack profile CVSS 4.0 · 5.1

Attack vector: Network
Complexity: Low
Attack requirements: None
Privileges needed: None
User interaction: Active
Confidentiality: None
Integrity: None
Availability: None

Raw vector

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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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Fix and advisories

https://github.com/Cotonti/Cotonti/pull/1908

References

NVD record · CVE.org record