CVE-2024-21392Network attack vector

Service interruption via leaked HTTP/2 CONNECT streams

Published Mar 12, 2024 · Updated May 3, 2025

Resource exhaustion in Microsoft .NET, Visual Studio, and PowerShell allows remote attackers to interrupt applications via crafted HTTP/2 traffic. System.Net.Http mishandles HTTP/2 extended CONNECT stream completion, retaining stream resources until crafted exchanges exhaust the application. Exploitation requires an affected application to process attacker-controlled HTTP/2 extended CONNECT traffic; the bounded consequence is service interruption.

CVSS severity7.5
High
EPSS probability3.09%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Microsoft .NET, Visual Studio, and PowerShell allows remote attackers to interrupt applications via crafted HTTP/2 traffic. System.Net.Http mishandles HTTP/2 extended CONNECT stream completion, retaining stream resources until crafted exchanges exhaust the application. Exploitation requires an affected application to process attacker-controlled HTTP/2 extended CONNECT traffic; the bounded consequence is service interruption.

The record

CVE
CVE-2024-21392
Published
Mar 12, 2024
Updated
May 3, 2025
Vendor
Microsoft
Product
PowerShell 7.3
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 12, 2024CVE publishedPublication date reported by the CVE source.
  2. May 3, 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=7.3.0 <7.3.12

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · PowerShell 7.3version=7.3.0 <7.3.12
Microsoft · Microsoft Visual Studio 2022 version 17.8version=17.8.0 <17.8.8
Microsoft · Microsoft Visual Studio 2022 version 17.6version=17.6.0 <17.6.13
Microsoft · Microsoft Visual Studio 2022 version 17.4version=17.4.0 <17.4.17
Microsoft · .NET 8.0version=8.0 <8.0.3
Microsoft · .NET 7.0version=7.0.0 <7.0.17
Microsoft · PowerShell 7.4version=7.4.0 <7.4.1
Microsoft · Microsoft Visual Studio 2022 version 17.9version=17.0 <17.9.3

Published CVSS scores

7.5Microsoft CorporationCVSS: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-400Uncontrolled Resource Consumption
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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