CVE-2026-81421
Received Received - Intake

Server-Side Request Forgery in ddfourtwo Sentry-Selfhosted-MCP

Publication date: 2026-08-27

Last updated on: 2026-08-27

Assigner: VulDB

Description
A security flaw has been discovered in ddfourtwo sentry-selfhosted-mcp 0.4.0. The affected element is an unknown function of the component raw_sentry_api. The manipulation of the argument endpoint results in server-side request forgery. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.

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Meta Information

Published
2026-08-27
Last Modified
2026-08-27
Generated
2026-08-27
AI Q&A
2026-08-27
EPSS Evaluated
N/A
NVD
CVE-2026-81421
EUVD
EUVD-2026-66829

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
ddfourtwo sentry-selfhosted-mcp 0.4.0

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-918 The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Attack-Flow Graph

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Executive Summary

This is a Server-Side Request Forgery (SSRF) vulnerability in ddfourtwo sentry-selfhosted-mcp 0.4.0. The raw_sentry_api component allows attackers to manipulate the endpoint argument to send HTTP requests to arbitrary destinations, including internal or loopback addresses, instead of just the configured Sentry API. The exploit can be triggered remotely and has been publicly disclosed.

Detection Guidance

To detect this SSRF vulnerability in ddfourtwo sentry-selfhosted-mcp 0.4.0, check if the raw_sentry_api tool is exposed and if it accepts absolute URLs without validation. Review server logs for outbound requests to unexpected destinations, especially internal or loopback addresses. Use network monitoring tools to inspect HTTP requests originating from the MCP server.

Impact Analysis

An attacker could access internal services, APIs, or sensitive data if the server can reach them. This may lead to data breaches, unauthorized actions, or service disruption. The impact depends on what internal resources the server can access.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data, violating GDPR's data protection principles or HIPAA's security requirements. Non-compliance risks include legal penalties, reputational damage, and loss of trust.

Mitigation Strategies

Immediately restrict access to the raw_sentry_api tool to authorized users only. Block outbound requests to loopback addresses, private IP ranges, and unauthorized domains at the network level. Implement strict endpoint allowlisting and reject absolute URLs in the endpoint argument. Add authentication, logging, and rate limiting to the MCP server.

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