CVE-2026-63833: ntfs3: reject direct userspace writes to reserved $LX* xattrs

criticalCVSS 9.8CVE-2026-63833

CSIRTS triage

vendor: Linux product: ntfs3Other

What: This vulnerability rejects direct userspace writes to reserved $LX* xattrs.
Who is affected: Deployments using the ntfs3 filesystem.
Urgency: Remediation is important to maintain filesystem integrity, with no current exploitation reported.
Action: Ensure that direct userspace writes to reserved $LX* xattrs are rejected.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: critical — CVSS 9.8
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-63833

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-638330.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-63833	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for ntfs3

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

medium[UPDATE] [medium] Linux Kernel (ntfs3): Vulnerability allows information disclosurecert-bund · 2026-07-31
highCVE-2026-63833: In the Linux kernel, the following vulnerability has been resolved: ntfs3: reject direct users…nvd · 2026-07-19