CVE-2026-49856: CWE-918: Server-Side Request Forgery (SSRF) in vmoranv jshookmcp
@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.
AI Analysis
Technical Summary
The vmoranv jshookmcp MCP server version 0.3.1 implements a central SSRF authorization policy that blocks private, loopback, link-local, and reserved network targets unless explicitly authorized. However, the ICMP probe and traceroute tools do not enforce this policy properly; they resolve targets and invoke native ICMP/traceroute sinks directly. This allows an MCP client with access to an active network domain to perform internal network probing, exposing internal reachability and route mapping information. The vulnerability is addressed in version 0.3.2.
Potential Impact
An attacker with MCP client access to an active network domain can leverage this SSRF vulnerability to map internal network routes and reachability by probing internal addresses. The impact is limited to information disclosure of internal network topology and does not affect confidentiality, integrity, or availability of data or services directly.
Mitigation Recommendations
Upgrade to vmoranv jshookmcp version 0.3.2 or later, where this SSRF vulnerability is fixed. Patch status is not explicitly confirmed in the advisory, but the description states version 0.3.2 fixes the issue. No other mitigations are indicated.
CVE-2026-49856: CWE-918: Server-Side Request Forgery (SSRF) in vmoranv jshookmcp
Description
@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.
CVSS v3.1
Score 4.3medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vmoranv jshookmcp MCP server version 0.3.1 implements a central SSRF authorization policy that blocks private, loopback, link-local, and reserved network targets unless explicitly authorized. However, the ICMP probe and traceroute tools do not enforce this policy properly; they resolve targets and invoke native ICMP/traceroute sinks directly. This allows an MCP client with access to an active network domain to perform internal network probing, exposing internal reachability and route mapping information. The vulnerability is addressed in version 0.3.2.
Potential Impact
An attacker with MCP client access to an active network domain can leverage this SSRF vulnerability to map internal network routes and reachability by probing internal addresses. The impact is limited to information disclosure of internal network topology and does not affect confidentiality, integrity, or availability of data or services directly.
Mitigation Recommendations
Upgrade to vmoranv jshookmcp version 0.3.2 or later, where this SSRF vulnerability is fixed. Patch status is not explicitly confirmed in the advisory, but the description states version 0.3.2 fixes the issue. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-01T22:03:19.640Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7ddec3bf8831d5395cfc25
Added to database: 08/13/2026, 15:12:03 UTC
Last enriched: 08/13/2026, 15:59:42 UTC
Last updated: 08/13/2026, 17:57:33 UTC
Views: 3
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