Vulnerability Description
Uptime Kuma through 2.5.8 contains a race condition in the Socket.IO first-run setup handler that allows unauthenticated attackers to create an additional administrator account. Attackers can send concurrent setup requests during the bcrypt hashing window to bypass the empty user table check, then modify monitors, API keys, and enable disableAuth.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://abraxaslabs.tech/research/uptime-kuma-setup-toctou
- https://github.com/louislam/uptime-kuma
- https://github.com/louislam/uptime-kuma/blob/2.5.8/server/server.js#L705-L722
- https://www.vulncheck.com/advisories/uptime-kuma-through-2.5.8-race-condition-ad
FAQ
What is CVE-2026-119552?
CVE-2026-119552 is a vulnerability with a CVSS score of 4.8 (MEDIUM). Uptime Kuma through 2.5.8 contains a race condition in the Socket.IO first-run setup handler that allows unauthenticated attackers to create an additional administrator account. Attackers can send con...
How severe is CVE-2026-119552?
CVE-2026-119552 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-119552?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.