9.9
CRITICAL CVSS 3.1
CVE-2026-30921
OneUptime Synthetic Monitor RCE via exposed Playwright browser object
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.

INFO

Published Date :

March 10, 2026, 5:40 p.m.

Last Modified :

March 12, 2026, 1:44 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-30921 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Hackerbay oneuptime
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL MITRE-CVE
CVSS 3.1 CRITICAL [email protected]
Solution
Update OneUptime to version 10.0.20 or later to fix the RCE vulnerability.
  • Update OneUptime to version 10.0.20 or later.
  • Apply vendor patches for the synthetic monitor component.
  • Review code execution environments for untrusted input.
  • Restrict privileges for project users submitting Playwright code.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-30921.

URL Resource
https://github.com/OneUptime/oneuptime/security/advisories/GHSA-4j36-39gm-8vq8 Exploit Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-30921 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-30921 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-30921 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-30921 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Mar. 12, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:hackerbay:oneuptime:*:*:*:*:*:*:*:* versions up to (excluding) 10.0.20
    Added Reference Type GitHub, Inc.: https://github.com/OneUptime/oneuptime/security/advisories/GHSA-4j36-39gm-8vq8 Types: Exploit, Vendor Advisory
  • New CVE Received by [email protected]

    Mar. 10, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
    Added CWE CWE-749
    Added Reference https://github.com/OneUptime/oneuptime/security/advisories/GHSA-4j36-39gm-8vq8
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.