Netatalk has Integer Underflow → Stack Buffer Overflow in copydir() (CVE-2026-45699) | HOL Guard CVE

High · CVSS 7.5CVE-2026-45699

Netatalk has Integer Underflow → Stack Buffer Overflow in copydir()

Answer in brief

CVE-2026-45699 records a High severity (CVSS 7.5) vulnerability in Netatalk has Integer Underflow → Stack Buffer Overflow in copydir(). The current sources do not mark it as known exploited. The current feed maps Netatalk/netatalk (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 14, 2026Updated Sep 18, 2026Source checked Sep 29, 2026First seen by HOL Aug 14, 2026Material review Sep 18, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Netatalk/netatalk (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Netatalk/netatalkgeneric	>=3.1.19 <4.4.3	4.4.3

Recommended response

Check inventory. Check lockfiles and deployed manifests for Netatalk/netatalk.
Review the reported fix. Update Netatalk/netatalk to 4.4.3 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 14, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 14, 2026

Sources and claim methodology

Upstream source 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 copydir() function of Netatalk's afpd daemon due to an integer underflow in the calculation of the remaining buffer size used for path construction. copydir() 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 track available buffer space using srem and drem for source and destination paths. Incorrect arithmetic causes both srem and drem to underflow to SIZE_MAX. Consequently, boundary checks against strlen(de->d_name) always pass, allowing strcpy() to append filenames into nearly full stack buffers. Version 4.4.3 patches the issue. As a workaround, configure each AFP shared volume to be structured as a single file system, in other words no subdirectory of a shared volume should be a mount point for a different file system.

Quoted source text, attributed separately from HOL analysis.