What is CVE-2021-3985?

CVE-2021-3985 is a critical-severity vulnerability in Kevinpapst Kevinpapst/kimai2, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2021-12-01.

How severe is CVE-2021-3985?

Critical severity. CVSS v3 base score is 9.0 out of 10.

Is CVE-2021-3985 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Kevinpapst Kevinpapst/kimai2

CVE-2021-3985

kimai2 is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-12-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (68.4th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 68th percentile — 68.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.013 · change: +0.000

Affected products

Kevinpapst Kevinpapst/kimai2 — versions unspecified
Kimai Kimai2

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

References

huntr.dev/bounties/89d6c3de-efbd-4354-8cc8-46e999e4c5a4 (Exploit, Patch, Third Party Advisory)
github.com/kevinpapst/kimai2/commit/76e09447c85e762882126b49626a4fe4d93fe8b5 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-3985?: CVE-2021-3985 is a critical-severity vulnerability in Kevinpapst Kevinpapst/kimai2, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2021-12-01.
How severe is CVE-2021-3985?: Critical severity. CVSS v3 base score is 9.0 out of 10.
Is CVE-2021-3985 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.