CVE-2026-24781: VM2 Has Sandbox Breakout Through Inspect Function

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 1.2%, percentile 68: FIRST’s model estimates a 1.2% chance of exploitation activity in the next 30 days, higher than 68% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes vm2 (npm) <= 3.10.3, fixed in 3.11.0. Check your lockfile, including transitive dependencies.

What it is

vm2 is an open source vm/sandbox for Node.js. Prior to version 3.11.0, VM2 suffers from a sandbox breakout vulnerability through the inspect function. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system. This issue has been patched in version 3.11.0.

From the GitHub advisory

Summary

VM2 suffers from a sandbox breakout vulnerability through the inspect function. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.

Details

The node inspect method allows to log details of objects. To get to the details, the implementation unwraps proxies. The unwrapped values can be extracted using the this.seen of the stylize function. This allows to get access to the internal proxy handler of VM2 which contains the sandbox object. Since the access to the handler is itself wrapped by a VM2 proxy, accessing the sandbox object in the proxy handler will result in a wrapped sandbox object given into the sandbox. This allows to write a wrapped host object to the wrapped sandbox object and read the raw host object from the raw sandbox object bypassing the proxy bridge.

PoC

Weakness type: CWE-94, CWE-693, CWE-653.

Product: vm2 (npm) · Assigned by: GitHub_M · Published: 2026-05-04

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 1.19% probability of exploitation activity in the next 30 days; percentile 68.

Timeline

• 2026-05-04 — CVE record published by GitHub_M
• 2026-05-05 — GitHub-reviewed advisory GHSA-v37h-5mfm-c47c published (critical)
• 2026-07-15 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. access.redhat.com access.redhat.com
2. access.redhat.com access.redhat.com

Vulnerability records

1. GitHub Advisory GHSA-v37h-5mfm-c47c github.com
2. CVE.org record CVE-2026-24781 cve.org
3. NVD entry CVE-2026-24781 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com
4. github.com github.com
5. github.com github.com
6. access.redhat.com access.redhat.com
7. RHBZ#2466531 bugzilla.redhat.com
8. security.access.redhat.com security.access.redhat.com

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