CVE-2025-62504 — Use After Free in Envoy

CWE-416 — Use After FreeCWE-825 — Expired Pointer Dereference2 documents2 sources
Severity
7.5HIGHNVD
EPSS
0.0%
top 95.08%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
1
Envoyproxy Envoy
Timeline
PublishedOct 16

Description

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 servic…

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 3.9 | Impact: 3.6

Affected Packages2 packages

▶NVDenvoyproxy/envoy1.34.0 — 1.34.10+3
▶CVEListV5envoyproxy/envoy1.33.11+3

📋Vendor Advisories

1
Red Hat
envoy: Envoy Lua filter use-after-free when oversized rewritten response body causes crash↗2025-10-16
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