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GHSA-g2r8-wvmj-jf5w: `nx graph` dev server permissive CORS policy

mediumCVSS 5.9CVE-2026-54753
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

Source
GitHub Security Advisories (INTL · database · site)
Severity
medium — CVSS 5.9
Published
2026-07-31
Last updated
2026-07-31
Exploitation
Not in CISA KEV at last sync

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.

Referenced CVEs

CVECSIRTS overviewExternal
CVE-2026-54753coverage & exploitation statusNVD · CVE.org

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