CVE-2026-49856 (GCVE-0-2026-49856)
Vulnerability from cvelistv5 – Published: 2026-08-13 15:00 – Updated: 2026-08-13 17:27
VLAI
EPSS
VEX
Title
@jshookmcp/jshook: ICMP probe and traceroute skip local-network SSRF authorization
Summary
@jshookmcp/jshook is an MCP server that gives AI agents tools for JavaScript analysis and security research. In version 0.3.1, he network domain has a central SSRF authorization policy that blocks private, loopback, link-local, and reserved targets unless an explicit authorization object allows private network access. The policy is enforced by raw HTTP/TCP/TLS RTT tools, but the ICMP probe and traceroute tools resolve the target and invoke the native ICMP/traceroute sink directly. An MCP client with access to an active network domain can therefore ask the jshookmcp server to probe internal addresses even when local SSRF access is disabled for the other raw network tools. This exposes an internal reachability and route mapping primitive from the server network position. Version 0.3.2 fixes the issue.
Severity
4.3 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 17:25 UTC
CWE
- CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/vmoranv/jshookmcp/security/adv… | x_refsource_CONFIRM |
| https://github.com/vmoranv/jshookmcp/commit/02111… | x_refsource_MISC |
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