CVE-2026-48044

HIGH

Envoy Zstd Decompressor: Ratio Check at Wrong Loop Depth lead to memory explosion

Title source: cna
STIX 2.1

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.23.0 until 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a vulnerability has been identified in Envoy's zstd decompressor implementation (ZstdDecompressorImpl). When zstd decompression is enabled, processing a specially crafted, highly compressed zstd payload can lead to massive memory allocation. An attacker can exploit this to cause severe memory exhaustion, potentially resulting in an Out-Of-Memory (OOM) kill and Denial of Service (DoS) for the Envoy proxy. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1.

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0032
EPSS Percentile 24.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-409
Status published
Products (5)
envoyproxy/envoy 1.23.0 - 1.35.13
envoyproxy/envoy >= 1.23.0, < 1.35.11
envoyproxy/envoy >= 1.36.0, < 1.36.7
envoyproxy/envoy >= 1.37.0, < 1.37.3
envoyproxy/envoy >= 1.38.0, < 1.38.1
Published Jun 26, 2026
Tracked Since Jun 26, 2026