Vulnerability in Louislam Uptime-Kuma
CVE-2026-119552
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.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/louislam/uptime-kuma/blob/2.5.8/server/server.js (technical-description)
- abraxaslabs.tech/research/uptime-kuma-setup-toctou (third-party-advisory)
- github.com/louislam/uptime-kuma (product)
- www.vulncheck.com/advisories/uptime-kuma-through-2.5.8-race-condition-admin-cre… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-119552?
- CVE-2026-119552 is a medium-severity vulnerability in Louislam Uptime-Kuma, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 4.8/10. Published 2026-10-30.
- How severe is CVE-2026-119552?
- Medium severity. CVSS v3 base score is 4.8 out of 10.