CVE-2026-30861: CVE-2026-30861: Remote Code Execution via Incomplete Command Blacklist in Tencent WeKnora

CVE-2026-30861: Remote Code Execution via Incomplete Command Blacklist in Tencent WeKnora

Vulnerability ID: CVE-2026-30861
CVSS Score: 10.0
Published: 2026-03-07

Tencent WeKnora versions 0.2.5 through 0.2.9 contain a critical vulnerability in the Model Context Protocol (MCP) configuration logic. The application implements an incomplete argument blacklist for the stdio transport type, allowing attackers to bypass validation using Node.js execution flags. Since WeKnora permits unrestricted user registration by default, remote attackers can register an account, configure a malicious MCP service, and achieve arbitrary code execution with the privileges of the application process.

TL;DR

CVE-2026-30861 is a critical RCE vulnerability in Tencent WeKnora caused by an incomplete command blacklist in the MCP stdio transport validation. Attackers bypass restrictions using the Node.js -p flag via npx to execute arbitrary system commands. The vendor patched this in version 0.2.10 by completely removing the stdio transport feature.

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⚠️ Exploit Status: POC

Technical Details

• CWE ID: CWE-78, CWE-184
• Attack Vector: Network
• CVSS v3.1 Score: 10.0
• EPSS Score: 0.00209
• Impact: Remote Code Execution
• Exploit Status: poc
• CISA KEV: False

Affected Systems

• Tencent WeKnora
• WeKnora: 0.2.5 - 0.2.9 (Fixed in: 0.2.10)
• WeKnora: 2.0.5 - 2.0.9 (Fixed in: 2.0.10)

Code Analysis

Commit: 57d6fea

Final patch disabling stdio transport type completely

Commit: f7900a5

Previous incomplete fix introducing the flawed blacklist

Exploit Details

• GitHub Security Advisory: Public PoC documenting the Node.js -p flag bypass

Mitigation Strategies

• Upgrade WeKnora to version 0.2.10 / 2.0.10 or later.
• Disable open user registration to prevent unauthenticated access to the API.
• Implement WAF rules to block requests containing "transport_type": "stdio".

Remediation Steps:

1. Verify the current running version of WeKnora via the application console or container tags.
2. Backup the WeKnora database and configuration files.
3. Deploy the updated container image or binary for version 0.2.10.
4. Audit the mcp_services table in the database and remove any unknown or suspicious service definitions.
5. Review access logs for unauthorized access to the /api/v1/mcp-services endpoint.

References

• GitHub Security Advisory GHSA-r55h-3rwj-hcmg
• NVD Record for CVE-2026-30861
• OSV Entry for GHSA-r55h-3rwj-hcmg

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Read the full report for CVE-2026-30861 on our website for more details including interactive diagrams and full exploit analysis.