GHSA-r9pm-gxmw-wv6p is a high-severity (CVSS 8.6) CWE-693 vulnerability in vm2. O3 Security confirms whether GHSA-r9pm-gxmw-wv6p is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
NodeVM network builtin exclusions bypass via internal _http_client and _http_server
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for GHSA-r9pm-gxmw-wv6p.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-r9pm-gxmw-wv6p plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 0 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
vm2npmDescription
Summary
NodeVM supports excluding public network builtins from the wildcard builtin option. With this configuration direct access to http, https, http2, net, dgram, tls, dns, and dns/promises is blocked.
However, Node.js also exposes underscored internal HTTP builtins such as _http_client and _http_server. These are not blocked when the public modules are excluded.
Sandboxed code can use these internal builtins to make outbound HTTP requests and open listening HTTP sockets even though the public network modules are denied.
Note: This is not host RCE. It is a network capability bypass that can lead to SSRF-style access to internal services.
Details
The wildcard builtin expansion is based on Node.js builtin module names:
const BUILTIN_MODULES = (nmod.builtinModules || Object.getOwnPropertyNames(process.binding('natives')))
.filter(s=>!s.startsWith('internal/') && !DANGEROUS_BUILTINS.has(s));
Public modules can be excluded with -name:
if (builtins.indexOf(`-${name}`) === -1) {
addDefaultBuiltin(res, name, hostRequire);
}
But excluding http and net does not exclude internal siblings such as:
_http_client
_http_server
_tls_wrap
These internal modules expose network primitives.
Confirmed examples:
require('_http_client').ClientRequest(...)performs an outbound HTTP request to a host-local service whilehttpandnetare blocked.require('_http_server').Server(...).listen(...)opens a listening HTTP socket whilehttpandnetare blocked.
PoC
Tested on:
vm2: 3.11.2
Node.js: v25.9.0
Run from the vm2 repository root:
node poc/internal-http-builtin-network-bypass.js
internal-http-builtin-network-bypass.js
The PoC first confirms the intended restrictions work then bypasses them:
require("_http_client").ClientRequest(...)
This performs an HTTP request to a host-local service and reads the response.
It also confirms:
require("_http_server").Server(...).listen(0)
This opens a listening HTTP socket from inside the sandbox.
<img width="951" height="623" alt="Screenshot 2026-05-10 at 1 07 39 PM" src="https://github.com/user-attachments/assets/21bfb1ff-dd15-423a-92c4-0337cd07816c" />Impact
An attacker who can run untrusted JavaScript inside NodeVM with this affected builtin configuration can regain network access even when the application attempted to block network modules.
This can allow SSRF-style access to localhost services, metadata endpoints, internal admin panels, or other network resources reachable from the host process.
Suggested fix
Treat underscored internal network modules as dangerous or link their availability to the public module they wrap.
At minimum, exclude related internal modules such as:
_http_agent
_http_client
_http_common
_http_incoming
_http_outgoing
_http_server
_tls_common
_tls_wrap
Alternatively, deny underscored Node.js internals from wildcard builtin expansion by default.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | vm2 | all versions | 3.11.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vm2. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update vm2 to 3.11.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r9pm-gxmw-wv6p is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-r9pm-gxmw-wv6p is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-r9pm-gxmw-wv6p. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability has been rated as Moderate for Red Hat Developer Hub and Red Hat Ansible Automation Platform. The vm2 sandbox exists as a transitive dependency in Red Hat Developer Hub and is only utilized during build time. The sandbox is therefore not exposed on the production code path. Exploitation of this…
Frequently Asked Questions
Is GHSA-r9pm-gxmw-wv6p in your dependencies?
O3 detects GHSA-r9pm-gxmw-wv6p across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.