Four MCP servers exposed unauthenticated CVE vulnerabilities

From Monday to Tuesday evening, four Model Context Protocol servers successively published CVE records, all with the issue that exposed tools are accessible without authentication. These involve the Bifrost MCP gateway (CVE-2026-90898, CVSS 9.8), mysql-mcp-server (CVE-2026-59971, 10.0), IBM mcp-contextforge-gateway (CVE-2026-53710, 10.0), and @zereight/mcp-gitlab (CVE-2026-61560, 9.8). The NVD ingested all four within about 35 hours, all with status Received and scores self-assessed by the CNA. The author said that as of publication, no analysis of these four had been found on Hacker News or Dev.to.