Critical severity · published Sep 15, 2026
CVE-2026-52824
Kimai: Default APP_SECRET in Docker Image Enables Cookie Forgery and Account Takeover
9.1
CVSS
1.3%
EPSS
No
On KEV
Description
Kimai is an open-source time tracking application. Prior to 2.58.0, the official Docker image sets APP_SECRET to the public value change_this_to_something_unique in Dockerfile, and .docker/entrypoint.sh neither replaces nor rejects that value before Symfony uses it as kernel.secret. An unauthenticated attacker who reaches a deployment that did not override APP_SECRET, knows a username, correctly guesses the account ID associated with that username, and targets an account without active two-factor authentication can forge HMAC-protected authentication artifacts, including KIMAI_REMEMBER cookies and login links, to access the account without its password. The updated entrypoint generates and persists a random secret when no safe operator-provided value exists. This issue is fixed in version 2.58.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KI
kimai · kimai
< 2.58.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-52824
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-52824
github.com
https://github.com/kimai/kimai/commit/31a8f887a5cda517db7b4320a7ad997c87d08601
github.com
https://github.com/kimai/kimai/pull/5952
github.com
https://github.com/kimai/kimai/releases/tag/2.58.0
github.com
https://github.com/kimai/kimai/security/advisories/GHSA-jr9p-4h4j-6c58
www.kimai.org
https://www.kimai.org/en/security/ghsa-jr9p-4h4j-6c58
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