VulnSocial

CVE-2026-73550(envoyproxy / envoy)

LOWCVSS 7.5 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

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.

envoyproxy CVEsBack to dashboard
0.0/ 10 priority

Sources & remediation

Patch / fix
Exploit / PoC references
Other references
Weakness type (CWE)
CWE-401

Priority

LOW

Exploitation

NONE

PoC

YES

Patch

AVAILABLE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • envoy

Threat summary

  • 1 mentions across 1 observed day

What's happening

  • 1 total mentions across 1 day

Affected systems

Vendors
envoyproxy
Products
envoy

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-10-15: 110-15
Referenced assets1 URL
By indicator
Full discourse1 post
  • Hugo | DevOps | Cybersecurity 🇱🇻@HugoValters

    CVE-2026-73550 Envoy CVSS 7.5: HTTP/2 Host header bypasses limit accounting, unauthenticated DoS via HPACK indexing. Fixed in 1.36.10, 1.37.6, 1.38.4, 1.39.1. Patch now. https://www.valtersit.com/cve/CVE-2026-73550 #CVE #infosec #Envoy #Envoyproxy #CVEALERT #CVE #infosec #Linux #XSS #valtersit #snippet #SysAdmin #cybersecurity #devsecops #devops #developer #100daysofcode #git #github #gitlab #redteam #blueteam #ethicalhacker #cybersecurityawareness #cybersecuritynews #cybersecuritytips #python #hacker #kali #ubuntu #debian #docker

    0000032
    1.0K followersView on X
CPE platform detail1 entries

1 of 1 entries

PartVendorProductVersionTarget SWTarget HW
Appenvoyproxyenvoy---

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