OneUptime:: node:vm sandbox escape in probe allows any project member to achieve RCE

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.9 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

• CVE-2026-27574: 0.56% estimated exploitation activity in the next 30 days; percentile 46.74 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary OneUptime lets project members write custom JavaScript that runs inside monitors. The problem is it executes that code using Node.js's built-in vm module, which Node.js itself documents as "not a security mechanism — do not use it to run untrusted code." The classic one-liner escape gives full access to the underlying process, and since the probe runs with host networking and holds all cluster credentials in its environment, this turns into a full cluster compromise for anyone who can register an account. Details The vulnerable code is in Common/Server/Utils/VM/VMRunner.ts at line 55: The JavaScript that reaches this call comes straight from the monitor's customCode field, which is only validated as Zod.string().optional() in Common/Types/Monitor/MonitorStep.ts:531. No AST analysis, no keyword filtering, nothing — just a string that goes directly into vm.runInContext(). Both CustomCodeMonitor.ts and SyntheticMonitor.ts import VMRunner directly inside the probe process. So…

Published by the source

24 Feb 2026, 16:00 UTC

Last modified by the source

24 Feb 2026, 16:24 UTC

Source last checked

26 Oct 2026, 12:42 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-v264-xqh4-9xmm

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-v264-xqh4-9xmm

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-v264-xqh4-9xmm

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# Patch Next advisory brief: CVE-2026-27574

Advisory: OneUptime:: node:vm sandbox escape in probe allows any project member to achieve RCE
IDs: CVE-2026-27574, GHSA-v264-xqh4-9xmm
Record: https://patchnext.com/advisories/cve-2026-27574 (revision 3, source checked 26 Oct 2026, 12:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @oneuptime/common 10.0.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @oneuptime/common: affected < 10.0.0; fixed in 10.0.0

## Suggested inspection (read-only)
- `npm ls @oneuptime/common --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @oneuptime/common.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-v264-xqh4-9xmm (GitHub-reviewed advisory GHSA-v264-xqh4-9xmm lists affected ranges: npm @oneuptime/common >=0 <10.0.0)
- Verified: https://osv.dev/vulnerability/GHSA-v264-xqh4-9xmm (OSV record GHSA-v264-xqh4-9xmm lists affected ranges: npm @oneuptime/common >=0 <10.0.0 (fixed))

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