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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/kimai/kimai/security/advisories/GHSA-jrc6-fmhw-fpq2
https://www.vulncheck.com/advisories/kimai-before-2.54.0-username-enumeration-via-timing-oracle

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-26 05:18

Updated : 2026-08-31 20:52

NVD link : CVE-2026-80199

Mitre link : CVE-2026-80199

CVE.ORG link : CVE-2026-80199

JSON object : View

Products Affected

No product.

CWE

CWE-208

Observable Timing Discrepancy

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