CVE-2024-38440Public exploitNetwork attack vector

Unauthenticated service crash via one-byte heap write

Published Jun 16, 2024 · Updated Nov 3, 2025

Heap buffer overflow in affected Netatalk releases allows remote attackers to crash afpd through a crafted FPLoginExt request. The uams_dhx_pam.c handler trusts the parsed length and passes a fixed KEYSIZE slice to BN_bin2bn, causing a one-byte null write beyond the heap allocation. Exposure requires PAM support and the uams_dhx.so authentication module; demonstrated impact is an afpd segmentation fault under specific heap layouts or ASAN.

CVSS severity7.3
High
EPSS probability0.88%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Heap buffer overflow in affected Netatalk releases allows remote attackers to crash afpd through a crafted FPLoginExt request. The uams_dhx_pam.c handler trusts the parsed length and passes a fixed KEYSIZE slice to BN_bin2bn, causing a one-byte null write beyond the heap allocation. Exposure requires PAM support and the uams_dhx.so authentication module; demonstrated impact is an afpd segmentation fault under specific heap layouts or ASAN.

The record

CVE
CVE-2024-38440
Published
Jun 16, 2024
Updated
Nov 3, 2025
Vendor
Netatalk
Product
Netatalk
Classifications
CWE-193, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 16, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <3.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Netatalk · Netatalkversion=0 <3.2.1

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.3NetatalkCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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 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 exploitPublished

Weakness, pattern, technique

CWE-193Off-by-one Error
T1499Endpoint Denial of Service

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo