Go to homepageCyberStrike

Menu

Star on GitHub · 3.2k
Sign inDownload

CVE-2026-27203

8.3 · HIGH

eBay API MCP Server is an open source local MCP server providing AI assistants with comprehensive access to eBay's Sell APIs.

Published Feb 21, 2026CWE-15EPSS 0.50%

Overview

CVE-2026-27203 is a high-severity vulnerability. It was published on February 21, 2026 and has a CVSS 3.1 base score of 8.3 (HIGH).

This vulnerability has a CVSS 3.1 base score of 8.3, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.

Technical description

eBay API MCP Server is an open source local MCP server providing AI assistants with comprehensive access to eBay's Sell APIs. All versions are vulnerable to Environment Variable Injection through the updateEnvFile function. The ebay_set_user_tokens tool allows updating the .env file with new tokens. The updateEnvFile function in src/auth/oauth.ts blindly appends or replaces values without validating them for newlines or quotes. This allows an attacker to inject arbitrary environment variables into the configuration file. An attacker can inject arbitrary environment variables into the .env file. This could lead to configuration overwrites, Denial of Service, and potential RCE. There was no fix for this issue at the time of publication.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References

GitHubgithub.com/YosefHayim/ebay-mcp/commit/aab0bda75ea9dd27aa37d0d8524d7cf41b3c4a9aGitHubgithub.com/YosefHayim/ebay-mcp/security/advisories/GHSA-97rm-xj73-33jh

How CyberStrike helps

Frequently asked questions

What is CVE-2026-27203?

CVE-2026-27203 is a high-severity vulnerability. It was published on February 21, 2026 and has a CVSS 3.1 base score of 8.3 (HIGH).

How severe is CVE-2026-27203?

This vulnerability has a CVSS 3.1 base score of 8.3, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.

How do I fix or remediate CVE-2026-27203?

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2026-27203?

CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-27203 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.

Related HIGH CVEs from 2026

View all
Browse by year2026202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999