Vulnerability · CVE-2026-63833
In the Linux kernel, the following vulnerability has been resolved: ntfs3: reject direct userspace writes to reserved $LX* xattrs NTFS3 uses $LXUID, $LXGID, $LXMOD and…
Published Jul 19, 2026 · catalog updated Oct 22, 2026 · linux kernel
Check if you run it
No confirmed exploitation is on record for CVE-2026-63833. EPSS is 0.11%. Act only if a listed version of linux kernel is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.1
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.11%
- Remediation
- Version ranges on file
- Affected products
- cpe linux/linux kernel
In the Linux kernel, the following vulnerability has been resolved: ntfs3: reject direct userspace writes to reserved $LX* xattrs NTFS3 uses $LXUID, $LXGID, $LXMOD and $LXDEV as internal WSL permission metadata and reloads them into i_uid, i_gid and i_mode from ntfs_get_wsl_perm(). Because the empty-prefix xattr handler also lets file owners call setxattr() on these names directly, an unprivileged writer on a writable ntfs3 mount can plant root ownership and S_ISUID on their own file and gain euid 0 after inode reload. Reject direct userspace writes to the reserved $LX* names. Internal ntfs3 metadata updates are unchanged because ntfs_save_wsl_perm() writes them via ntfs_set_ea() directly. [almaz.alexandrovich@paragon-software.com: added an additional check for non privileged users]
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe linux/linux kernel< 5.15.211
- cpe linux/linux kernel< 6.1.177
- cpe linux/linux kernel< 6.12.95
- cpe linux/linux kernel< 6.18.38
- cpe linux/linux kernel< 6.6.144
- cpe linux/linux kernel< 7.1.3
How to fix CVE-2026-63833
Recommended remediation
Affected version ranges suggest a fixed boundary. Verify against the vendor advisory for your release.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-63833. EPSS is 0.11%. Act only if a listed version of linux kernel is installed.
Which versions are affected?
Compare what you have installed with linux/linux kernel < 5.15.211; linux/linux kernel < 6.1.177; linux/linux kernel < 6.12.95; linux/linux kernel < 6.18.38. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-862: Missing Authorization. EPSS 0.11%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Jul 19, 2026 · NIST NVD
Detected
In the Linux kernel, the following vulnerability has been resolved: ntfs3: reject direct userspace writes to reserved $LX* xattrs NTFS3 uses $LXUID, $LXGID, $LXMOD and $LXDEV as internal WSL permission metadata and reloads them into i_uid, i_gid and i_mode from ntfs_get_wsl_perm(). Because the empty-prefix xattr handler also lets file owners call setxattr() on these names directly, an unprivileged
Oct 22, 2026 · NIST NVD
Updated
In the Linux kernel, the following vulnerability has been resolved: ntfs3: reject direct userspace writes to reserved $LX* xattrs NTFS3 uses $LXUID, $LXGID, $LXMOD and $LXDEV as internal WSL permission metadata and reloads them into i_uid, i_gid and i_mode from ntfs_get_wsl_perm(). Because the empty-prefix xattr handler also lets file owners call setxattr() on these names directly, an unprivileged
Sources
- CVE.orgVulnerability recordCVE-2026-63833
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-63833
30-day exploitation probability 0.11%
first.org - NIST NVDVulnerability recordCVE-2026-63833
In the Linux kernel, the following vulnerability has been resolved: ntfs3: reject direct userspace writes to reserved $LX* xattrs NTFS3 uses $LXUID, $LXGID, $LXMOD and $LXDEV as internal WSL permission metadata and reloads them into i_uid, i_gid and i_mode from ntfs_get_wsl_per
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 23, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.