{"id":"CVE-2026-14539","summary":"Denial of Service via Unrestricted Payload Buffering in MCP Toolbox","details":"An allocation of resources without limits vulnerability in the HTTP handler component of Google mcp-toolbox versions up to and including 1.4.0 allows an unauthenticated attacker to cause a denial of service (DoS). The /mcp endpoint handler reads incoming payloads directly into system memory using an unrestricted buffer loop (io.ReadAll) without applying defensive constraints such as http.MaxBytesReader or pre-read Content-Length enforcement. By submitting a single, massive HTTP request body, an attacker can linearly consume available host memory until the runtime process is terminated by an Out-Of-Memory (OOM) error.","modified":"2026-08-12T03:51:28.862112940Z","published":"2026-07-31T01:45:35.468Z","database_specific":{"cna_assigner":"Google","cwe_ids":["CWE-770"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/14xxx/CVE-2026-14539.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/14xxx/CVE-2026-14539.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-14539"},{"type":"FIX","url":"https://github.com/googleapis/mcp-toolbox/pull/3216"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/googleapis/mcp-toolbox","events":[{"introduced":"0"},{"fixed":"45c0f86ce0199a8aed9c980370dd2c03f2684f5a"}],"database_specific":{"source":["AFFECTED_FIELD","CPE_RANGE"],"cpe":"cpe:2.3:a:google:mcp_toolbox_for_databases:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0.0.0"},{"last_affected":"1.4.0"},{"introduced":"0"},{"fixed":"1.5.0"}]}}],"versions":["v1.4.0","v1.3.0","v1.2.0","v1.1.0","v1.0.0","v0.32.0","v0.31.0","v0.30.0","v0.29.0","v0.28.0","v0.27.0","v0.26.0","v0.25.0","v0.24.0","v0.23.0","v0.22.0","v0.21.0","v0.20.0","v0.19.1","v0.18.0","v0.17.0","v0.16.0","v0.15.0","v0.14.0","v0.13.0","v0.12.0","v0.11.0","v0.10.0","v0.9.0","v0.8.0","v0.7.0","v0.6.0","v0.5.0","v0.4.0","v0.3.0","v0.2.1","v0.2.0","v0.1.0","v0.0.5","v0.0.4","v0.0.3","v0.0.2","v0.0.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-14539.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U"}]}