CVE-2026-30921criticalCWE-749

CVE-2026-30921: critical vulnerability in oneuptime

OneUptime Synthetic Monitor RCE via exposed Playwright browser object

Published · Updated

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 10epss 0.5%
OneUptime is a solution for monitoring and managing online services. Prior to 10.0.20, OneUptime Synthetic Monitors allow low-privileged project users to submit custom Playwright code that is executed on the oneuptime-probe service. In the current implementation, this untrusted code is run inside Node's vm and is given live host Playwright objects such as browser and page. This creates a distinct server-side RCE primitive: the attacker does not need the classic this.constructor.constructor(...) sandbox escape. Instead, the attacker can directly use the injected Playwright browser object to reach browser.browserType().launch(...) and spawn an arbitrary executable on the probe host/container. This vulnerability is fixed in 10.0.20.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Affected products
OneUptime · oneuptime