Envoy Zstd Decompressor: Ratio Check at Wrong Loop Depth lead to memory explosion
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-48044
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 7 Nov 2026, 02:55 UTC · Revision 1
Source evidence
Envoy Zstd Decompressor: Ratio Check at Wrong Loop Depth lead to memory explosion
core-osv · Original sourcePublished 26 Jun 2026, 17:31 UTC
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.
osv:CVE-2026-48044
Complete source record
{
"id": "6d669e15d10f7902dc47682433e2975a7705f1cb731e15c3df6e46fc35738e65",
"url": "https://osv.dev/vulnerability/CVE-2026-48044",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Envoy Zstd Decompressor: Ratio Check at Wrong Loop Depth lead to memory explosion",
"summary": "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.",
"evidence": "osv:CVE-2026-48044",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-48044",
"aliases": [
"BIT-envoy-2026-48044",
"CVE-2026-48044",
"GHSA-m3p9-47wh-88wg"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/envoyproxy/envoy",
"type": "GIT",
"events": [
{
"introduced": "ce49c7f65668a22b80d1e83c35d170741bb8d46a"
},
{
"fixed": "adb998f2875986005be294d10231a9c9a497e30d"
},
{
"introduced": "63ee0dc79dce88117c6bd2df5a742f8eb67ea980"
},
{
"fixed": "57198c441a298a75097c690726d90974549a9778"
},
{
"introduced": "6d9bb7d9a85d616b220d1f8fe67b61f82bbdb8d3"
},
{
"fixed": "f97695a50e11f5ff6719e129a466bf9204b64a7f"
},
{
"introduced": "f1dd21b16c244bda00edfb5ffce577e12d0d2ec2"
},
{
"fixed": "0ebfcfe5b0484b89ca85b761da9e05ce75dbda8d"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.23.0"
},
{
"fixed": "1.35.13"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.36.0"
},
{
"fixed": "1.36.9"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.37.0"
},
{
"fixed": "1.37.5"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.38.0"
},
{
"fixed": "1.38.3"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v1.38.2",
"v1.37.4",
"v1.36.8",
"v1.35.12",
"v1.38.1",
"v1.37.3",
"v1.36.7",
"v1.35.11",
"v1.38.0",
"v1.37.2",
"v1.36.6",
"v1.35.10",
"v1.37.1",
"v1.36.5",
"v1.35.9",
"v1.37.0",
"v1.36.4",
"v1.35.8",
"v1.36.3",
"v1.35.7",
"v1.35.6",
"v1.36.2",
"v1.36.1",
"v1.35.5",
"v1.36.0",
"v1.35.4",
"v1.35.3",
"v1.35.2",
"v1.35.1",
"v1.35.0",
"v1.34.0",
"v1.33.0",
"v1.32.0",
"v1.31.0",
"v1.30.0",
"v1.29.0",
"v1.28.0",
"v1.27.0",
"v1.26.0",
"v1.25.0",
"v1.24.0",
"v1.23.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48044.json"
}
}
],
"modified": "2026-10-28T02:30:48.985327748Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48044.json",
"https://github.com/envoyproxy/envoy/security/advisories/GHSA-m3p9-47wh-88wg",
"https://nvd.nist.gov/vuln/detail/CVE-2026-48044"
],
"provider_metadata": {
"cwe_ids": [
"CWE-409"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48044.json"
}
},
"related_cves": [
{
"value": "CVE-2026-48044",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 517545,
"published_at": "2026-06-26T17:31:37.602+00:00"
}