CVE-2026-53765

chrome-devtools-mcp: daemon.pid write follows symlinks in /tmp fallback runtime directory

MEDIUM
6.1
CVSS Score
Published: June 24, 2026 at 09:30 PM UTC
Updated: October 25, 2026 at 11:10 PM UTC
2 products affected across 2 vendorsChrome Devtools McpChrome Devtools Mcp

Using chrome-devtools-mcp by ChromeDevTools?

Get instant alerts when new vulnerabilities affect chrome-devtools-mcp - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.1
Exploit prediction
EPSS 0.1%
SSVC
No known exploit

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0.20.0 ≤ v < 1.1.0
Affected range stops below 1.1.0, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.1.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

x_refsource_CONFIRMExploitThird Party Advisory
Source: cverecord
https://github.com/ChromeDevTools/chrome-devtools-mcp/security/advisories/GHSA-3pvj-jv98-qhjq

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.1MEDIUMGitHub_M
Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
LOW
Vector?

Quick Info

StatusANALYZED
CWE
CWE-59

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card