Security readout for executives and security teams
Plain-English summary
A malicious NTFS disk image or filesystem could make NTFS-3G consume stack through recursive calls, causing a crash or denial of service. The public bundle points to NTFS-3G versions before 2021.8.22. This is mainly an availability risk for systems that mount or inspect untrusted NTFS media or images.
Executive priority
Treat this as a targeted availability issue, not an emergency internet-wide compromise signal. Prioritize updates on workstations, forensic systems, file-processing services, and kiosks that handle untrusted NTFS media or disk images.
Technical view
CVE-2021-39257 describes a crafted NTFS image with an unallocated bitmap triggering an endless recursive call chain starting from ntfs_attr_pwrite in NTFS-3G before 2021.8.22, leading to stack consumption. The provided sources do not include CVSS, CWE, or detailed affected CPE data.
Likely exposure
Exposure is most likely where NTFS-3G is installed and used to mount, repair, index, scan, or process NTFS filesystems from removable media, uploaded disk images, forensic samples, or other untrusted sources.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation. Exploitation requires a crafted NTFS image or filesystem reaching vulnerable NTFS-3G processing. Public details support denial of service, not code execution or privilege escalation.
Researcher notes
Evidence is sparse: no CVSS, CWE, CPE, exploit status, or deep technical advisory text is included in the bundle. Analysis should stay scoped to stack consumption via recursive NTFS-3G processing before 2021.8.22.
Mitigation direction
- Update NTFS-3G to version 2021.8.22 or a vendor-patched package.
- Apply Debian, Gentoo, or relevant distribution security updates where applicable.
- Restrict mounting or automated processing of untrusted NTFS media until updated.
- Review vendor advisories for environment-specific package names and fixed versions.
Validation and detection
- Inventory systems and containers with NTFS-3G installed.
- Confirm installed NTFS-3G versions are 2021.8.22 or vendor-patched.
- Check whether services automatically process uploaded or removable NTFS images.
- Verify distribution security advisories were applied on managed Linux hosts.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-39257 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/tuxera/ntfs-3g/releasesCVE reference
- https://github.com/tuxera/ntfs-3g/security/advisories/GHSA-q759-8j5v-q5jpCVE reference
- DSA-4971CVE reference · vendor-advisory
- [debian-lts-announce] 20211116 [SECURITY] [DLA 2819-1] ntfs-3g security updateCVE reference · mailing-list
- GLSA-202301-01CVE reference · vendor-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.