CRITICAL

CVE-2026-63732

CVSS v3

9.9

CRITICAL

EPSS Score

0.7%

exploit probability

CISA KEV

No

known exploited

Exploitation

SSVC status

Description

9router 0.4.59 (fixed in 0.4.60) contains a chain of vulnerabilities: a hardcoded default password (123456) that authenticates any fresh installation, a bypass of the LOCAL_ONLY network gate via a spoofed Host header, and unvalidated arguments passed to child_process.spawn() when registering MCP plugins. A remote, unauthenticated attacker can log in with the default credential, spoof the Host header to reach local-only routes, and register a malicious MCP plugin (e.g. node -e <payload>) to achie

Technical details

CVSS v3 Vector
3.1
Published
7/23/2026
Last Modified
7/23/2026

Frequently asked questions

What is CVE-2026-63732?

9router 0.4.59 (fixed in 0.4.60) contains a chain of vulnerabilities: a hardcoded default password (123456) that authenticates any fresh installation, a bypass of the LOCAL_ONLY network gate via a spoofed Host header, and unvalidated arguments passed to child_process.spawn() when registering MCP plugins. A remote, unauthenticated attacker can log in with the default credential, spoof the Host header to reach local-only routes, and register a malicious MCP plugin (e.g. node -e <payload>) to achie

Is CVE-2026-63732 actively exploited?

Active exploitation of CVE-2026-63732 has not been confirmed. The EPSS score is 0.7%, indicating the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-63732?

CVE-2026-63732 has a CVSS v3 base score of 9.9 (CRITICAL severity), with vector string 3.1.

Is CVE-2026-63732 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.