CVE-2026-48044

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

HIGH

7.5

CVSS Score

Published: June 26, 2026 at 05:31 PM UTC

Updated: October 25, 2026 at 05:10 PM UTC

1 product affected across 1 vendorEnvoy

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Severity

HIGH7.5

Exploit prediction

EPSS 0.5%

SSVC

No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Envoy · Envoyproxy

95%

1.23.0 ≤ v < 1.35.131.36.0 ≤ v < 1.36.91.37.0 ≤ v < 1.37.51.38.0 ≤ v < 1.38.3

Affected range stops below 1.35.11, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.35.13, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.36.7, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.36.9, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.37.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.37.5, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.38.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.38.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://github.com/envoyproxy/envoy/security/advisories/GHSA-m3p9-47wh-88wg

References (1)

x_refsource_CONFIRMMitigationVendor AdvisoryExploit

Source: cverecord

https://github.com/envoyproxy/envoy/security/advisories/GHSA-m3p9-47wh-88wg

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHGitHub_M

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: NONE
Availability: HIGH

Vector?

Quick Info

StatusANALYZED

CWE

CWE-409

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