Vulnerability Description
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 Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Hackerbay | Oneuptime | < 10.0.20 |
Related Weaknesses (CWE)
References
- https://github.com/OneUptime/oneuptime/security/advisories/GHSA-4j36-39gm-8vq8ExploitVendor Advisory
FAQ
What is CVE-2026-30921?
CVE-2026-30921 is a vulnerability with a CVSS score of 9.9 (CRITICAL). 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...
How severe is CVE-2026-30921?
CVE-2026-30921 has been rated CRITICAL with a CVSS base score of 9.9/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-30921?
Check the references section above for vendor advisories and patch information. Affected products include: Hackerbay Oneuptime.