GHSA-g2r8-wvmj-jf5w: `nx graph` dev server permissive CORS policy
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, < 22.7.2 and >= 23.0.0-beta.0, < 23.0.0-beta.2
- Patched: 22.7.2+ (backport) and 23.0.0 (first in 23.0.0-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 mus
Details
Original advisory: https://github.com/advisories/GHSA-g2r8-wvmj-jf5w
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-547530.81% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 53% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-54753 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
More from GitHub Security Advisories
- mediumGHSA-jr6p-8pjj-mfx6: Capsule has an incomplete fix of CVE-2026-22872: TenantResource RawItems and Generators s…2026-07-31
- mediumGHSA-68cj-mvg9-rgm2: Capsule: CapsuleConfiguration NodeMetadata regex fields lack webhook validation, allowing…2026-07-31
- mediumGHSA-ff84-5f28-78qj: re2: Out-of-bounds heap read in `exec`/`test`/`match` via attacker-influenced `lastIndex`…2026-07-31
- mediumGHSA-6hxr-mr5r-9836: re2: Global `String.prototype.match` with an empty-matchable pattern never advances → inf…2026-07-31
- mediumGHSA-x83g-979r-f5fh: Sylius Mollie Plugin has unauthenticated IDOR that leaks order token and customer PII2026-07-31