Vulnerability · Published Mar 9, 2026 · Assigned by GitHub_M

CVE-2026-30921OneUptime Synthetic Monitor RCE via exposed Playwright browser object

Critical 10.0

In plain English

A critical-severity security flaw in oneuptime from OneUptime. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)10.0Critical
Exploit odds (30 days)0.5%top 57.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
npm@oneuptime/common10.0.20GHSA-4j36-39gm-8vq8

Affected products (as reported)

VendorProductVersions
OneUptime oneuptime < 10.0.20

Weakness: CWE-749 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

References