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archive/Patch now/AIR-2026-1006
closedclosed 31 Mar 2026Patch now2 Disclosed vulnerabilityAI

CVE-2026-34237: Hardcoded Wildcard CORS Vulnerability in MCP Java SDK

MCP Java SDK

A hardcoded wildcard CORS vulnerability was discovered in the MCP Java SDK prior to versions 0.83.0, 1.0.1, and 1.1.1. The issue has been addressed by the vendor in updated releases.

disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why

CVSS
6.1
EPSS
<0.01 · top 86% · 2026-11-13
EPSS scores by FIRST
fix status
Fix status unknown
first report
31 Mar 2026
last update
31 Mar 2026
CVE ids
CVE-2026-34237other records

Timeline · 1

  1. 31 Mar 2026CVE-2026-34237: MCP Java SDK is the official Java SDK for Model Context Protocol servers and clients.

Sources · 1

Advisories and databases

  1. 2026-03-31
    CVE-2026-34237: MCP Java SDK is the official Java SDK for Model Context Protocol servers and clients.
    NVD · nvd.nist.gov/vuln/detail/CVE-2026-34237

Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.

Classification

lane
Patch now
AI role
Attack on AI
categories
Infrastructure vulnerability
severity
2 · Disclosed vulnerability
fix status
Fix status unknown
targets
Framework / tooling
owasp llm top 10
LLM03:2025 Supply Chain
mitre atlas
no technique for these categories
tags
corsmcp
dates
happened 31 Mar 2026 · first reported 31 Mar 2026
origin
NVD
Vulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
record
confidence 0.95 · created 2026-10-18 10:04Z · updated 2026-10-18 10:04Z

Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned

Copy a brief

This record as a short Markdown brief, for a ticket, a chat or a coding agent.

the brief as text
# CVE-2026-34237: Hardcoded Wildcard CORS Vulnerability in MCP Java SDK

https://gcdradar.vercel.app/incidents/cve-2026-34237-hardcoded-wildcard-cors-vulnerability-in-mcp · AIR-2026-1006 · closed 2026-03-31

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-03-31
- AI role: Attack on AI
- Products: MCP Java SDK
- CVE ids: CVE-2026-34237
- CVSS: 6.1

## Summary

A hardcoded wildcard CORS vulnerability was discovered in the MCP Java SDK prior to versions 0.83.0, 1.0.1, and 1.1.1. The issue has been addressed by the vendor in updated releases.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-03-31: CVE-2026-34237: MCP Java SDK is the official Java SDK for Model Context Protocol servers and clients. (https://nvd.nist.gov/vuln/detail/CVE-2026-34237)

## Sources

- 2026-03-31 NVD: CVE-2026-34237: MCP Java SDK is the official Java SDK for Model Context Protocol servers and clients. https://nvd.nist.gov/vuln/detail/CVE-2026-34237

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.

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