Description
Netatalk is a Free and Open Source file server suite for Unix-like operating systems. In versions 3.1.19 through 4.4.2, a stack-based buffer overflow exists in the deletedir() function of Netatalk's afpd daemon due to an integer underflow in the calculation of the remaining buffer size used for path construction. deletedir() is a utility function called when a file operation crosses a device boundary inside an AFP shared volume, which the standard library's renameat() cannot handle. The function attempts to prevent buffer overflows by tracking available space in a size_t remain variable. However, the arithmetic used to compute remain results in an unsigned integer underflow, causing the variable to become SIZE_MAX. Because of this, the subsequent boundary check always evaluates as safe, allowing an unbounded strcpy() operation to copy attacker-controlled filenames into a nearly full stack buffer. Version 4.4.3 patches the issue.
Published: 2026-08-17
Score: 7.5 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

Netatalk, a Unix‑like file server suite, contains a stack‑based buffer overflow in the deletedir() function of its afpd daemon. The flaw stems from an integer underflow that turns the remain variable into SIZE_MAX, causing an unbounded strcpy() to copy attacker‑controlled filenames into a nearly full stack buffer. Exploiting this bug can lead to arbitrary code execution on the affected system.

Affected Systems

Vulnerable versions of Netatalk include releases from 3.1.19 through 4.4.2. The issue is present in the Netatalk suite, notably in the afpd daemon that handles AFP shared volumes.

Risk and Exploitability

The CVSS score of 7.5 indicates a high severity. EPSS is not available and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is inferred to be through AFP file operations that cross a device boundary, a scenario requiring authenticated AFP access; the flaw can lead to remote code execution if successfully triggered.

Generated by OpenCVE AI on August 17, 2026 at 19:28 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Update to Netatalk version 4.4.3 or later, which contains the integer underflow fix and eliminates the buffer overflow.
  • If an immediate update is not possible, restrict AFP traffic from untrusted networks or disable the afpd daemon until the patch is applied to prevent the vulnerability from being exercised.
  • Monitor system logs for abnormal afpd activity and set alerts for attempts to perform file operations across device boundaries to detect potential exploitation attempts.

Generated by OpenCVE AI on August 17, 2026 at 19:28 UTC.

Tracking

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-62801 netatalk security update
History

Mon, 17 Aug 2026 19:45:00 +0000

Type Values Removed Values Added
First Time appeared Netatalk
Netatalk netatalk
Vendors & Products Netatalk
Netatalk netatalk

Mon, 17 Aug 2026 18:45:00 +0000

Type Values Removed Values Added
Description Netatalk is a Free and Open Source file server suite for Unix-like operating systems. In versions 3.1.19 through 4.4.2, a stack-based buffer overflow exists in the deletedir() function of Netatalk's afpd daemon due to an integer underflow in the calculation of the remaining buffer size used for path construction. deletedir() is a utility function called when a file operation crosses a device boundary inside an AFP shared volume, which the standard library's renameat() cannot handle. The function attempts to prevent buffer overflows by tracking available space in a size_t remain variable. However, the arithmetic used to compute remain results in an unsigned integer underflow, causing the variable to become SIZE_MAX. Because of this, the subsequent boundary check always evaluates as safe, allowing an unbounded strcpy() operation to copy attacker-controlled filenames into a nearly full stack buffer. Version 4.4.3 patches the issue.
Title Netatalk has Integer Underflow → Stack Buffer Overflow in deletedir()
Weaknesses CWE-191
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Subscriptions

Netatalk Netatalk
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-17T19:29:54.873Z

Reserved: 2026-05-13T04:38:01.165Z

Link: CVE-2026-45698

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-17T19:16:30.703

Modified: 2026-08-17T19:16:30.703

Link: CVE-2026-45698

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-17T19:30:17Z

Weaknesses
  • CWE-191

    Integer Underflow (Wrap or Wraparound)