CVE-2021-39255 Memory corruption in n/a

What is CVE-2021-39255?

CVE-2021-39255 is a medium-severity memory corruption vulnerability in Debian Debian Linux, published on 7 Sep 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A crafted NTFS image can trigger an out-of-bounds read, caused by an invalid attribute in ntfs_attr_find_in_attrdef, in NTFS-3G < 2021.8.22.

Weakness: CWE-125, CWE-20

Which versions are affected by CVE-2021-39255?

It affects 2 products.

Products include Debian Debian Linux, Tuxera Ntfs-3g.

How do I fix CVE-2021-39255?

Upgrade to a fixed version.

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

Is CVE-2021-39255 being exploited?

There is no known exploitation of CVE-2021-39255 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

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• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

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

Also known as AZL-6760, DEBIAN-CVE-2021-39255, GHSA-w39f-4cm2-25x2, UBUNTU-CVE-2021-39255.