7.5

CVE-2026-73550

Exploit

Envoy: HTTP/2 Discarded Host Header 200 GB Header-Copy OOM in Envoy

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy copies every decoded HTTP/2 Host header value before discarding it when :authority is already present. The discarded value bypasses saveHeader, so its bytes and count are not charged against request header limits. An unauthenticated client can use HPACK indexing to submit many references to a large Host value across a bounded number of streams, forcing extreme header-copy allocation and causing the proxy to be out-of-memory killed. The relevant scope boundary is that the demonstrated amplification uses HTTP/2 HPACK and the duplicate Host discard behavior. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Envoyproxy ≫ Envoy Version < 1.36.10
Envoyproxy ≫ Envoy Version >= 1.37.0 < 1.37.6
Envoyproxy ≫ Envoy Version >= 1.38.0 < 1.38.4
Envoyproxy ≫ Envoy Version >= 1.39.0 < 1.39.1
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.88% 0.576
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-401 Missing Release of Memory after Effective Lifetime

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

https://github.com/envoyproxy/envoy/releases/tag/v1.36.10
Release Notes
https://github.com/envoyproxy/envoy/releases/tag/v1.37.6
Release Notes
https://github.com/envoyproxy/envoy/releases/tag/v1.38.4
Release Notes
https://github.com/envoyproxy/envoy/releases/tag/v1.39.1
Release Notes
https://github.com/envoyproxy/envoy/security/advisories/GHSA-qgf6-qvhw-4hvh
Vendor Advisory
Exploit
https://github.com/envoyproxy/envoy/commit/0910997f70e91d2d20c329bb507bfce44ce01f80
Patch
https://github.com/envoyproxy/envoy/commit/1fec994c868df008cdd4ae285aab58a196fd31f2
Patch
https://github.com/envoyproxy/envoy/commit/3fd0ffee7ac87adf3bc6e421656bb96310512300
Patch
https://github.com/envoyproxy/envoy/commit/fc75d8e35b0d11acbae18b63a0bd96e32e84f61b
Patch