{"api_version":"1","generated_at":"2026-08-30T21:11:16+00:00","cve":"CVE-2026-55557","urls":{"html":"https://cve.report/CVE-2026-55557","api":"https://cve.report/api/cve/CVE-2026-55557.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55557","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55557"},"summary":{"title":"browse-mcp: Arbitrary file write via unconfined download and state paths","description":"browse-mcp is a Playwright-based headless-browser MCP server for MCP-capable agents. Prior to 0.8.2, browser_download writes a fetched response body to join(save_dir, filename) without validating the caller-controlled save_dir, while browser_save_state and browser_load_state honor a caller-controlled path unchanged. A malicious MCP client, or an autonomous agent steered by indirect prompt injection on a visited page, can choose an arbitrary save_dir or state path and a URL whose response body becomes attacker-controlled file contents, allowing writes to any path the process can reach, including ~/.bashrc, autostart entries, or cron files, and potentially leading to host code execution. The force_fetch fallback also uses a raw fetch() that bypasses the BROWSE_MCP_ALLOWED_ORIGINS origin fence. This issue is fixed in version 0.8.2.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-08-25 17:17:32","updated_at":"2026-08-25 19:16:49"},"problem_types":["CWE-22","CWE-22 CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path 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