CVE-2024-30166Network attack vector

Information disclosure or service interruption via ClientHello over-read

Published Apr 3, 2024 · Updated Aug 2, 2024

Stack buffer over-read in Arm Mbed TLS 3.3.0 through 3.5.2 allows remote attackers to disclose memory or interrupt TLS servers. The TLS 1.3 ClientHello parser reads fewer than 256 bytes beyond a stack buffer while processing a crafted hello on servers supporting a PSK key exchange mode. The server must enable TLS 1.3 and an affected PSK mode; no authentication is required, and exploitation can disclose memory or stop the TLS service.

CVSS severity9.1
Critical
EPSS probability0.74%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack buffer over-read in Arm Mbed TLS 3.3.0 through 3.5.2 allows remote attackers to disclose memory or interrupt TLS servers. The TLS 1.3 ClientHello parser reads fewer than 256 bytes beyond a stack buffer while processing a crafted hello on servers supporting a PSK key exchange mode. The server must enable TLS 1.3 and an affected PSK mode; no authentication is required, and exploitation can disclose memory or stop the TLS service.

The record

CVE
CVE-2024-30166
Published
Apr 3, 2024
Updated
Aug 2, 2024
Vendor
Arm
Product
Mbed TLS
Classifications
CWE-121, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 3, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record 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=3.3.0 <3.6.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Arm · Mbed TLSversion=3.3.0 <3.6.0

Published CVSS scores

9.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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-121Stack-based Buffer Overflow
T1190Exploit Public-Facing Application

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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