Security Digest · Vulnerability record
CVE-2026-92935: vm2: NodeVM nesting guard accepts array-shaped require and permits host RCE
vm2 is a sandbox for running untrusted Node.js code.
CVSS 9.5 Critical EPSS 0.7% · p51 Check exposure
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.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.7%, percentile 51: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 51% 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) >= 3.11.4, <= 3.11.6, fixed in 3.11.7. Check your lockfile, including transitive dependencies. - Editorial verdict: Check exposure. vm2: 22 Critical Sandbox Escapes, Fixed in 3.12.2 — If anything outside your trust boundary can get code into vm2, upgrade to 3.12.2 today and plan to move that code out of process; if vm2 only runs your own code, upgrade on a normal cycle.
What it is
vm2 is a sandbox for running untrusted Node.js code. In versions >= 3.11.4 and
From the GitHub advisory
Summary
The NodeVM constructor computes hasRealRequireConfig using typeof requireOpts === 'object' && requireOpts !== null, so require: [] bypasses the guard intended to reject nesting without an explicit require configuration. makeResolverFromLegacyOptions() then destructures the array to undefined option fields and returns a resolver containing only NESTINGOVERRIDE.vm2. Any attacker whose JavaScript is executed by a downstream NodeVM configured with {nesting: true, require: []} can load the host vm2 module, create an inner NodeVM with an attacker-selected builtin allowlist, and execute commands as the host process. No equivalent plain-object validation exists in makeResolverFromLegacyOptions().
Array is converted into the vm2-only resolver: https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/resolver-compat.js#L205-L226
Nesting loader returns the host VM constructors: https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/nodevm.js#L640-L645
Proof of Concept
Weakness type: CWE-913.
Product: vm2 (npm) · Assigned by: VulnCheck · Published: 2026-09-17
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | vm2 | >= 3.11.4, <= 3.11.6 | 3.11.7 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| patriksimek | vm2 | 3.11.4 < 3.11.7 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulnCheck | 4.0 | 9.5 Critical | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| VulnCheck | 3.1 | 9 Critical | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H |
| GitHub | 3.1 | 9.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: high (needs special conditions)
- Attack requirements: present (depends on deployment conditions)
- Privileges required: none (no login)
- User interaction: none
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 none, automatable no, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.67% probability of exploitation activity in the next 30 days; percentile 51.
Timeline
- — erroneo.us brief: vm2: 22 Critical Sandbox Escapes, Fixed in 3.12.2
- — CVE record last updated
- — CVE record published by VulnCheck
- — GitHub-reviewed advisory GHSA-8hr7-r645-pc6w published (critical)
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
- GitHub Security Advisory (GHSA-8hr7-r645-pc6w) github.com
- Patch Commit github.com
Vulnerability records
- GitHub Advisory GHSA-8hr7-r645-pc6w github.com
- CVE.org record CVE-2026-92935 cve.org
- NVD entry CVE-2026-92935 nvd.nist.gov
Other references from the CVE record and advisory
- VulnCheck Advisory: vm2 NodeVM Remote Code Execution via Array-Shaped Require vulncheck.com
- github.com github.com
- github.com github.com