CVE-2022-29227Network attack vector

Remote proxy crash via stale stream reset

Published Jun 9, 2022 · Updated Apr 23, 2025

Use-after-free in Envoy before 1.22.1 allows remote attackers to crash the proxy through an HTTP internal redirect. During request replay, recreateStream relies on stale downstream completion state and resets an upstream stream that has already completed and been deleted. Exploitation requires internal redirects, a request body or trailers, and a redirect into an Envoy-generated local reply; the resulting use-after-free crashes the proxy.

CVSS severity7.5
High
EPSS probability1.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Envoy before 1.22.1 allows remote attackers to crash the proxy through an HTTP internal redirect. During request replay, recreateStream relies on stale downstream completion state and resets an upstream stream that has already completed and been deleted. Exploitation requires internal redirects, a request body or trailers, and a redirect into an Envoy-generated local reply; the resulting use-after-free crashes the proxy.

The record

CVE
CVE-2022-29227
Published
Jun 9, 2022
Updated
Apr 23, 2025
Vendor
Envoy Proxy
Product
Envoy
Classifications
CWE-416, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 9, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.22.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Envoy Proxy · Envoyversion=< 1.22.1

Published CVSS scores

7.5GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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