Vulnerability · Published Jun 24, 2026 · Assigned by GitHub_M
CVE-2026-53765chrome-devtools-mcp: daemon.pid write follows symlinks in /tmp fallback runtime directory
Medium 6.1
In plain English
A medium-severity security flaw in chrome-devtools-mcp from ChromeDevTools. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 1% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Chrome DevTools for agents (chrome-devtools-mcp) lets your coding agent control and inspect a live Chrome browser. From 0.20.0 until 1.1.0, The chrome-devtools-mcp daemon writes its PID file with fs.writeFileSync() to a deterministic runtime path. On typical macOS environments, and on Linux sessions where $XDG_RUNTIME_DIR is unset, that runtime path falls back to /tmp/chrome-devtools-mcp-<uid>/daemon.pid. Because the write does not use O_NOFOLLOW, a local low-privilege user on the same POSIX host can pre-create /tmp/chrome-devtools-mcp-<victim_uid>/daemon.pid as a symlink to a file writable by the victim. When the victim later starts daemon mode, fs.writeFileSync() follows the symlink and truncates the target file to the daemon PID string. This vulnerability is fixed in 1.1.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | chrome-devtools-mcp | 1.1.0 | GHSA-3pvj-jv98-qhjq |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ChromeDevTools | chrome-devtools-mcp | >= 0.20.0, < 1.1.0 |
Weakness: CWE-59 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L