CVE-2024-20685Network attack vector

Unauthenticated service interruption via InitialUEMessage length validation

Published Apr 9, 2024 · Updated May 3, 2025

Improper input validation in Microsoft Azure Private 5G Core before 2403.0-2 allows remote attackers to interrupt 5G service. The InitialUEMessage handler fails to validate a length parameter before processing untrusted signaling data, producing a denial-of-service condition. No authentication or user interaction is required, but exploitation has high complexity and interrupts availability across the 5G network.

CVSS severity5.9
Medium
EPSS probability5.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Microsoft Azure Private 5G Core before 2403.0-2 allows remote attackers to interrupt 5G service. The InitialUEMessage handler fails to validate a length parameter before processing untrusted signaling data, producing a denial-of-service condition. No authentication or user interaction is required, but exploitation has high complexity and interrupts availability across the 5G network.

The record

CVE
CVE-2024-20685
Published
Apr 9, 2024
Updated
May 3, 2025
Vendor
Microsoft
Product
Azure Private 5G Core
Classifications
CWE-130, T1498
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 9, 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=1.0.0 <2403.0-2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Azure Private 5G Coreversion=1.0.0 <2403.0-2

Published CVSS scores

5.9Microsoft CorporationCVSS:3.1/AV:N/AC:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-130Improper Handling of Length Parameter Inconsistency
T1498Network Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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