CVE-2025-62409

published 2025-10-16

CVE-2025-62409: Envoy is a cloud-native, open source edge and service proxy. Prior to 1.36.1, 1.35.5, 1.34.9, and 1.33.10, large requests and responses can potentially trigger…

Priority P3 44 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

Envoy is a cloud-native, open source edge and service proxy. Prior to 1.36.1, 1.35.5, 1.34.9, and 1.33.10, large requests and responses can potentially trigger TCP connection pool crashes due to flow control management in Envoy. It will happen when the connection is closing but upstream data is still coming, resulting in a buffer watermark callback nullptr reference. The vulnerability impacts TCP proxy and HTTP 1 & 2 mixed use cases based on ALPN. This vulnerability is fixed in 1.36.1, 1.35.5, 1.34.9, and 1.33.10.

Affected

8 ranges

Vendor	Product	Version range	Fixed in
envoyproxy	envoy	< 1.33.10	1.33.10
envoyproxy	envoy	< 1.33.11	1.33.11
envoyproxy	envoy	—	—
envoyproxy	envoy	—	—
envoyproxy	envoy	—	—
envoyproxy	envoy	—	—
envoyproxy	envoy	>= 1.34.0 < 1.34.9	1.34.9
envoyproxy	envoy	>= 1.35.0 < 1.35.5	1.35.5

CVSS provenance

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd v4.0 6.6 MEDIUM CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

vendor_redhat 6.6 MEDIUM

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CWE-476