{"id":"BIT-envoy-2025-62504","summary":"Envoy Lua filter use-after-free when oversized rewritten response body causes crash","details":"Envoy is an open source edge and service proxy. Envoy versions earlier than 1.36.2, 1.35.6, 1.34.10, and 1.33.12 contain a use-after-free vulnerability in the Lua filter. When a Lua script executing in the response phase rewrites a response body so that its size exceeds the configured per_connection_buffer_limit_bytes (default 1MB), Envoy generates a local reply whose headers override the original response headers, leaving dangling references and causing a crash. This results in denial of service. Updating to versions 1.36.2, 1.35.6, 1.34.10, or 1.33.12 fixes the issue. Increasing per_connection_buffer_limit_bytes (and for HTTP/2 the initial_stream_window_size) or increasing per_request_buffer_limit_bytes / request_body_buffer_limit can reduce the likelihood of triggering the condition but does not correct the underlying memory safety flaw.","aliases":["CVE-2025-62504","GHSA-gcxr-6vrp-wff3"],"modified":"2026-09-08T08:47:28.762194293Z","published":"2025-10-21T08:41:18.087Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*"]},"references":[{"type":"ADVISORY","url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-gcxr-6vrp-wff3"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-62504"}],"affected":[{"package":{"name":"envoy","ecosystem":"Bitnami","purl":"pkg:bitnami/envoy"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.33.12"},{"introduced":"1.34.0"},{"fixed":"1.34.10"},{"introduced":"1.35.0"},{"fixed":"1.35.6"},{"introduced":"1.36.0"},{"fixed":"1.36.2"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/envoy/BIT-envoy-2025-62504.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}],"schema_version":"1.9.0"}