GHSA-g2r8-wvmj-jf5w is a medium-severity (CVSS 5.9) CWE-749 vulnerability in nx. A fix is available for nx — see the affected versions and patch details below.
`nx graph` dev server permissive CORS policy
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-g2r8-wvmj-jf5w.
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-g2r8-wvmj-jf5w 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 376,715 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.
nxnpmDescription
Summary
The local HTTP server started by nx graph sent Access-Control-Allow-Origin: * on every response, letting any website a developer visited read the server's responses cross-origin — including the full project graph and the output of the /help endpoint, which runs a target's configured help command. The practical impact is typically cross-origin information disclosure, but can be arbitrary command injection in rare cases.
Severity
Exploitation requires the developer to be running nx graph and to visit an attacker page. Any execution beyond benign help commands also requires a malicious target to already be present in the workspace (see Details).
Affected & Patched Versions
Package: nx (npm).
- Affected:
>= 17.0.4, < 22.7.2and>= 23.0.0-beta.0, < 23.0.0-beta.2 - Patched:
22.7.2+ (backport) and23.0.0(first in23.0.0-beta.2)
The wildcard CORS header was introduced in 17.0.4; the /help execution endpoint in 19.4.0. The 21.x line is not patched — 21.x users should upgrade to 22.7.2 or later.
Details
nx graph starts a local server (default http://127.0.0.1:4211). Before the fix, its request handler set a wildcard CORS header on every response:
res.setHeader('Access-Control-Allow-Origin', '*');
The /help endpoint runs a target's configured command:
const command = target.metadata?.help?.command;
return execSync(command, { cwd: target.options?.cwd ?? workspaceRoot }).toString();
A GET /help is a CORS "simple request", so a malicious page could fetch() it with no preflight, and the wildcard header let the page read the result. This exposes the project graph (project names, file paths, dependencies, build configuration) and the output of any configured help command.
The command is not attacker-controlled through the request — it comes from the workspace's project configuration, and first-party plugins (jest, vite, cypress) populate it with benign, read-only help commands. For /help to run anything malicious, a target carrying a malicious help.command must already exist in the project graph, which can only be introduced by installing a malicious package or by altering the workspace's own code/configuration — both of which already grant code execution independent of this flaw.
The fix (#35494) removes the header; the browser's same-origin policy then blocks cross-origin reads.
References
- Fix: nrwl/nx#35494
- Introduced: nrwl/nx#20744 (CORS), nrwl/nx#26629 (
/help)
Credits
Thanks to Nozomu Sasaki (Paul) (@morimori-dev) for finding and responsibly reporting this issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | nx | ≥ 17.0.4&&< 22.7.2 | 22.7.2npm install nx@22.7.2 |
| 📦npm | nx | ≥ 23.0.0-beta.0&&< 23.0.0-beta.2 | 23.0.0-beta.2npm install nx@23.0.0-beta.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nx, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update nx to 22.7.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g2r8-wvmj-jf5w 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-g2r8-wvmj-jf5w can be triaged on real exposure rather than presence alone.
Tailored to GHSA-g2r8-wvmj-jf5w. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-g2r8-wvmj-jf5w in your dependencies?
O3 Security finds GHSA-g2r8-wvmj-jf5w across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.