{"id":"CVE-2026-53716","aliases":["BIT-envoy-gateway-2026-53716","GHSA-cxpq-8v7q-cg56","GO-2026-6006"],"url":"https://o3.security/vulnerability/CVE-2026-53716","summary":"Envoy Gateway: Wasm HTTP fetch decompresses gzip without output-size limit","details":"Vulnerability report without repro case. Repro case may be added later after harness is complete.\n\n**Preconditions (4):**\n- Tenant can create EnvoyExtensionPolicy (baseline)\n- Attacker hosts a gzip-bomb at a reachable URL\n- sha256 unset (optional field; check is post-decompression anyway)\n- No operator Wasm-URL allowlist (none exists in code)\n\n**Description**\n\ngetFileFromGZ calls io.ReadAll on a raw gzip.Reader (httpfetcher.go:216) with no output bound, while the compressed input is capped at 256 MiB (httpfetcher.go:139). The bytes originate from a tenant-controlled EnvoyExtensionPolicy.spec.wasm[].code.http.url (envoyextensionpolicy.go:1077 → cache.go:248 → httpfetcher.go:147 → :233), so an untrusted tenant can point at a ~10 MiB gzip-of-zeros and force ~10 GiB allocation in the shared controller process. All candidate guards execute either before the body is buffered or after decompression. OOM-kills, restarts, re-reconciles same CR, crash-loops — persistent cross-tenant control-plane outage with PR:L/AC:L and scope change → HIGH despite availability-only.","published":"2026-09-14T20:15:51.441Z","modified":"2026-10-21T02:58:30.227892162Z","cvss":{"score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.00685,"percentile":0.50913,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/envoyproxy/gateway","fixedVersion":"1.8.1"},{"ecosystem":"Go","name":"github.com/envoyproxy/gateway","fixedVersion":"1.7.4"}],"fix":{"url":"https://github.com/envoyproxy/gateway/commit/5a78db82b7cf4fc5bebbeda2c50952892038a464","label":"envoyproxy/gateway@5a78db8"},"references":[{"type":"WEB","url":"https://github.com/envoyproxy/gateway/releases/tag/v1.7.4"},{"type":"WEB","url":"https://github.com/envoyproxy/gateway/releases/tag/v1.8.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53716.json"},{"type":"ADVISORY","url":"https://github.com/envoyproxy/gateway/security/advisories/GHSA-cxpq-8v7q-cg56"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53716"},{"type":"FIX","url":"https://github.com/envoyproxy/gateway/commit/5a78db82b7cf4fc5bebbeda2c50952892038a464"},{"type":"FIX","url":"https://github.com/envoyproxy/gateway/commit/96e2b750868a459ace4b8b68e6a6e4fb0152b9b7"},{"type":"FIX","url":"https://github.com/envoyproxy/gateway/commit/b4737180c7e597490c6363075c565fa8cf24eead"},{"type":"FIX","url":"https://github.com/envoyproxy/gateway/pull/9171"},{"type":"FIX","url":"https://github.com/envoyproxy/gateway/pull/9172"},{"type":"FIX","url":"https://github.com/envoyproxy/gateway/pull/9173"},{"type":"PACKAGE","url":"https://github.com/envoyproxy/gateway"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:58:30.227892162Z"}}