8.1

CVE-2026-34742

Model Context Protocol Go SDK: DNS Rebinding Protection Disabled by Default for Servers Running on Localhost

The Go MCP SDK used Go's standard encoding/json. Prior to version 1.4.0, the Model Context Protocol (MCP) Go SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authentication with StreamableHTTPHandler or SSEHandler, a malicious website could exploit DNS rebinding to bypass same-origin policy restrictions and send requests to the local MCP server. This could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the user in those limited circumstances. This issue has been patched in version 1.4.0.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Lfprojects ≫ Mcp Go Sdk Version < 1.4.0
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.46% 0.362
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 8.1 2.8 5.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
security-advisories@github.com 7.6 0 0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
0b0ca135-0b70-47e7-9f44-1890c2a1c46c 8 1.6 5.8
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
CWE-1188 Initialization of a Resource with an Insecure Default

The product initializes or sets a resource with a default that is intended to be changed by the product's installer, administrator, or maintainer, but the default is not secure.

https://github.com/modelcontextprotocol/go-sdk/security/advisories/GHSA-xw59-hvm2-8pj6
Vendor Advisory
https://github.com/modelcontextprotocol/go-sdk/pull/760
Patch
Issue Tracking
https://github.com/modelcontextprotocol/go-sdk/commit/67bd3f2e2b53ce11a16db8d976cdb8ff1e986b6d
Patch
https://github.com/modelcontextprotocol/go-sdk/releases/tag/v1.4.0
Release Notes
https://access.redhat.com/errata/RHSA-2026:21772
https://access.redhat.com/security/cve/CVE-2026-34742
https://bugzilla.redhat.com/show_bug.cgi?id=2454608
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34742.json