What is CVE-2021-39257?

CVE-2021-39257 is a medium-severity vulnerability in Tuxera Ntfs-3g, classified under Uncontrolled Recursion. CVSS score: 5.5/10. Published 2021-09-07.

How severe is CVE-2021-39257?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Vulnerability in Tuxera Ntfs-3g

CVE-2021-39257

A crafted NTFS image with an unallocated bitmap can lead to a endless recursive function call chain (starting from ntfs_attr_pwrite), causing stack consumption in NTFS-3G < 2021.8.22.

Published 2021-09-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.004 (31.2th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Tuxera Ntfs-3g
Debian Linux — versions 9.0, 10.0, 11.0

Weakness classification (CWE)

CWE-674 — Uncontrolled Recursion

References

github.com/tuxera/ntfs-3g/releases (Third Party Advisory, Release Notes)
github.com/tuxera/ntfs-3g/security/advisories/GHSA-q759-8j5v-q5jp (Third Party Advisory)
www.debian.org/security/2021/dsa-4971 (vendor-advisory, Third Party Advisory)
lists.debian.org/debian-lts-announce/2021/11/msg00013.html (mailing-list, Mailing List, Third Party Advisory)
security.gentoo.org/glsa/202301-01 (vendor-advisory, Third Party Advisory)

Frequently asked questions

What is CVE-2021-39257?: CVE-2021-39257 is a medium-severity vulnerability in Tuxera Ntfs-3g, classified under Uncontrolled Recursion. CVSS score: 5.5/10. Published 2021-09-07.
How severe is CVE-2021-39257?: Medium severity. CVSS v3 base score is 5.5 out of 10.