XSS in Kimai
CVE-2026-40479
Kimai is an open-source time tracking application. In versions 1.16.3 through 2.52.0, the escapeForHtml() function in KimaiEscape.js does not escape double quote or single quote characters. When a user's profile alias is inserted into an HTML attribute context via the team member form prototype and rendered through innerHTML, this incomplete escaping allows HTML attribute injection. An authenticated user with ROLE_USER privileges can store a malicious alias that executes JavaScript in the browser of any administrator viewing the team form, resulting in stored XSS with privilege escalation. This issue has been fixed in version 2.53.0.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (10.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 11th percentile — 10.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: -0.000
Affected products
- Kimai — versions >= 1.16.3, < 2.53.0
Weakness classification (CWE)
References
- github.com/kimai/kimai/security/advisories/GHSA-g82g-m9vx-vhjg (Exploit, Vendor Advisory)
- github.com/kimai/kimai/releases/tag/2.53.0 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-40479?
- CVE-2026-40479 is a medium-severity vulnerability in Kimai, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-04-17.
- How severe is CVE-2026-40479?
- Medium severity. CVSS v3 base score is 5.4 out of 10.