How severe is CVE-2021-39261?

CVE-2021-39261 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-39261 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39261?

CVE-2021-39261 primarily affects Tuxera Ntfs-3g. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-39261?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-39261 published?

CVE-2021-39261 was published on 2021-09-07 and last updated on 2026-06-17.

CVE-2021-39261

CVE-2021-39261 is a high-severity vulnerability in Tuxera Ntfs-3g with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.9
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Tuxera Ntfs-3g
Published: 2021-09-07
Last modified: 2026-06-17

Description

A crafted NTFS image can cause a heap-based buffer overflow in ntfs_compressed_pwrite in NTFS-3G < 2021.8.22.

Frequently asked questions

What is CVE-2021-39261?: A crafted NTFS image can cause a heap-based buffer overflow in ntfs_compressed_pwrite in NTFS-3G < 2021.8.22.
How severe is CVE-2021-39261?: CVE-2021-39261 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-39261 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39261?: CVE-2021-39261 primarily affects Tuxera Ntfs-3g. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-39261?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-39261 published?: CVE-2021-39261 was published on 2021-09-07 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:tuxera:ntfs-3g:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

More vulnerabilities in Tuxera Ntfs-3g

CVE-2022-40284 — High (CVSS 7.8): A buffer overflow was discovered in NTFS-3G before 2022.10.3. Crafted metadata in an NTFS image can cause code…
CVE-2022-30789 — High (CVSS 7.8): A crafted NTFS image can cause a heap-based buffer overflow in ntfs_check_log_client_array in NTFS-3G through 2021.8.22.
CVE-2022-30788 — High (CVSS 7.8): A crafted NTFS image can cause a heap-based buffer overflow in ntfs_mft_rec_alloc in NTFS-3G through 2021.8.22.
CVE-2022-30786 — High (CVSS 7.8): A crafted NTFS image can cause a heap-based buffer overflow in ntfs_names_full_collate in NTFS-3G through 2021.8.22.
CVE-2022-30784 — High (CVSS 7.8): A crafted NTFS image can cause heap exhaustion in ntfs_get_attribute_value in NTFS-3G through 2021.8.22.
CVE-2021-46790 — High (CVSS 7.8): ntfsck in NTFS-3G through 2021.8.22 has a heap-based buffer overflow involving buffer+512*3-2. NOTE: the upstream…

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