CVE-2025-62504: 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…

PriorityP341high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.38%

30.1th percentile

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.

Affected

8 ranges

Vendor	Product	Version range	Fixed in
envoyproxy	envoy	< 1.33.12	1.33.12
envoyproxy	envoy	<= 1.33.11	—
envoyproxy	envoy	—	—
envoyproxy	envoy	—	—
envoyproxy	envoy	—	—
envoyproxy	envoy	>= 1.34.0 < 1.34.10	1.34.10
envoyproxy	envoy	>= 1.35.0 < 1.35.6	1.35.6
envoyproxy	envoy	>= 1.36.0 < 1.36.2	1.36.2

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

vendor_redhat6.5MEDIUM

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