CVE-2021-31439 Memory corruption in DiskStation Manager

What is CVE-2021-31439?

CVE-2021-31439 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 21 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Synology DiskStation Manager. Authentication is not required to exploit this vulnerablity. The specific flaw exists within the processing of DSI structures in Netatalk. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-12326.

Weakness: CWE-787, CWE-122

Which versions are affected by CVE-2021-31439?

It affects 3 products.

Products include Debian Debian Linux, Netatalk Netatalk, Synology Diskstation Manager.

How do I fix CVE-2021-31439?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-31439 being exploited?

There is no known exploitation of CVE-2021-31439 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-31439, GHSA-8292-4xc6-r7cv, UBUNTU-CVE-2021-31439.