Vulnerability in Kimai
CVE-2026-80199
Kimai before 2.54.0 contains a timing oracle vulnerability in TokenAuthenticator that allows unauthenticated attackers to enumerate valid usernames via X-AUTH-USER header. Attackers can measure response time differences when the password hasher runs only for existing users, enabling username enumeration with no login throttling protection.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.7% 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: 0.003 · change: +0.001
Affected products
Weakness classification (CWE)
References
- github.com/kimai/kimai/security/advisories/GHSA-jrc6-fmhw-fpq2 (vendor-advisory)
- www.vulncheck.com/advisories/kimai-before-2.54.0-username-enumeration-via-timin… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-80199?
- CVE-2026-80199 is a low-severity vulnerability in Kimai, classified under CWE-208. CVSS score: 3.7/10. Published 2026-08-26.
- How severe is CVE-2026-80199?
- Low severity. CVSS v3 base score is 3.7 out of 10.