CVE-2026-52824Public exploitNetwork attack vectorHinoki check available

Unauthenticated account takeover via default signing secret

Published Sep 15, 2026 · Updated Sep 15, 2026

Insecure default initialization in Kimai before 2.58.0 allows remote attackers to take over accounts via forged authentication artifacts. The official Dockerfile sets APP_SECRET to a public sentinel, and the entrypoint neither replaces nor rejects it before Symfony uses it as kernel.secret. Exploitation requires a reachable deployment that did not override the secret, a known username, a correctly guessed account ID, and an account without active two-factor authentication.

CVSS severity9.1
Critical
EPSS probability2.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Insecure default initialization in Kimai before 2.58.0 allows remote attackers to take over accounts via forged authentication artifacts. The official Dockerfile sets APP_SECRET to a public sentinel, and the entrypoint neither replaces nor rejects it before Symfony uses it as kernel.secret. Exploitation requires a reachable deployment that did not override the secret, a known username, a correctly guessed account ID, and an account without active two-factor authentication.

The record

CVE
CVE-2026-52824
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
Kimai
Product
Kimai
Classifications
CWE-1188, T1606.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.58.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Kimai · Kimaiversion=< 2.58.0

Published CVSS scores

7.4GitLab Advisory DatabaseCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
9.1GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-1188Initialization of a Resource with an Insecure Default
T1606.001Forge Web Credentials: Web Cookies

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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