{"cve":"CVE-2026-27203","nvd":{"published":"2026-02-21T00:16:17.463","modified":"2026-06-17T10:26:50.467","status":"Deferred","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H","score":8.3},"cwes":["CWE-15","CWE-74"],"references":["https://github.com/YosefHayim/ebay-mcp/commit/aab0bda75ea9dd27aa37d0d8524d7cf41b3c4a9a","https://github.com/YosefHayim/ebay-mcp/security/advisories/GHSA-97rm-xj73-33jh"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:24:17.937441719+00:00"},"epss":{"cve":"CVE-2026-27203","score":0.00401,"percentile":0.34381,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-97rm-xj73-33jh","url":"https://osv.dev/vulnerability/GHSA-97rm-xj73-33jh","summary":"eBay API MCP Server Affected by Environment Variable Injection ","modified":"2026-02-23T23:43:54.564312Z","packages":[{"ecosystem":"npm","name":"ebay-mcp","purl":"pkg:npm/ebay-mcp","ranges":["<=1.7.2"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}