CVE-2026-45698 Netatalk has Integer Underflow → Stack Buffer Overflow in deletedir()
An integer underflow in Netatalk's afpd daemon leads to a stack buffer overflow, allowing remote attackers to execute arbitrary code via crafted filenames.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45698?
CVE-2026-45698 is a high-severity vulnerability in netatalk, published on 17 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-191
Which versions are affected by CVE-2026-45698?
How do I fix CVE-2026-45698?
Upgrade to a fixed version.
Is CVE-2026-45698 being exploited?
There is no known exploitation of CVE-2026-45698 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-45698, GHSA-5443-v9xg-mqgv, UBUNTU-CVE-2026-45698.