CVE-2026-27203
8.3 · HIGHOverview
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.
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's AI-powered security agents can automatically detect CVE-2026-27203 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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