# CVE-2026-30957: OneUptime Synthetic Monitor RCE via exposed Playwright browser object

> A low-privileged user can execute arbitrary commands on the probe server by injecting code into Synthetic Monitors that accesses exposed Playwright objects.

- **Severity:** Critical 10.0 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Mar 2026
- **Updated:** 10 Mar 2026
- **Also known as:** GHSA-jw8q-gjvg-8w4q

## What is CVE-2026-30957?

CVE-2026-30957 is a critical code injection vulnerability in oneuptime, published on 10 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

OneUptime is a solution for monitoring and managing online services. Prior to 10.0.21, OneUptime Synthetic Monitors allow a low-privileged authenticated project user to execute arbitrary commands on the oneuptime-probe server/container. The root cause is that untrusted Synthetic Monitor code is executed inside Node's vm while live host-realm Playwright browser and page objects are exposed to it. A malicious user can call Playwright APIs on the injected browser object and cause the probe to spawn an attacker-controlled executable. This is a server-side remote code execution issue. It does not require a separate vm sandbox escape. This vulnerability is fixed in 10.0.21.

Weakness: CWE-749 (Exposed Dangerous Method or Function)

## Which versions are affected by CVE-2026-30957?

2 open source packages ship an affected version, including @oneuptime/common. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@oneuptime/common` | npm | All versions | 10.0.21 |
| `@oneuptime/common` | npm | All versions | 10.0.21 |

Products: Hackerbay Oneuptime.

## How do I fix CVE-2026-30957?

Upgrade @oneuptime/common to 10.0.21 or later.

## Is CVE-2026-30957 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-30957 exists.

## Other vulnerabilities in oneuptime

- [CVE-2026-33396](https://insights.sbomify.com/CVE-2026-33396/): Code injection in oneuptime (critical 10.0)
- [CVE-2026-32306](https://insights.sbomify.com/CVE-2026-32306/): OneUptime ClickHouse SQL Injection via Aggregate Query Parameters (critical 10.0)
- [CVE-2026-30956](https://insights.sbomify.com/CVE-2026-30956/): OneUptime has authorization bypass via client‑controlled is-multi-tenant-query header (critical 10.0)
- [CVE-2026-30887](https://insights.sbomify.com/CVE-2026-30887/): OneUptime Affected by Unsandboxed Code Execution in Probe Allows Any Project Member to Achieve RCE (critical 10.0)
- [CVE-2026-30921](https://insights.sbomify.com/CVE-2026-30921/): OneUptime Synthetic Monitor RCE via exposed Playwright browser object (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-30957 and fix it if it is affected.

What it is: CVE-2026-30957 is a critical code injection vulnerability in oneuptime, published on 10 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-30957 exists.

Affected packages and fixed versions:
- @oneuptime/common (npm): affected all versions; fixed in 10.0.21
- @oneuptime/common (npm): affected all versions; fixed in 10.0.21

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-30957/ (Markdown: https://insights.sbomify.com/CVE-2026-30957/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-30957
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-30957
- OSV: https://osv.dev/vulnerability/CVE-2026-30957

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-30957/
Summaries are generated and may contain mistakes; the official description above is the record.