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 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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/envoyproxy/envoy/security/advisories/GHSA-gcxr-6vrp-wff3	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::

History

29 Oct 2025, 19:19

Type	Values Removed	Values Added
References	~~() https://github.com/envoyproxy/envoy/security/advisories/GHSA-gcxr-6vrp-wff3 -~~	() https://github.com/envoyproxy/envoy/security/advisories/GHSA-gcxr-6vrp-wff3 - Vendor Advisory
CPE		cpe:2.3:a:envoyproxy:envoy::::::::
First Time		Envoyproxy envoy Envoyproxy

16 Oct 2025, 22:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-10-16 22:15

Updated : 2025-10-29 19:19

NVD link : CVE-2025-62504

Mitre link : CVE-2025-62504

CVE.ORG link : CVE-2025-62504

JSON object : View

Products Affected

envoyproxy

envoy

CWE

CWE-416

Use After Free

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