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 $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]

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/293a84fa40b3a1b3471c0545722724bc10973f76
https://git.kernel.org/stable/c/2c3cd6da4a14380ef79e34bd9dff7caf46687477
https://git.kernel.org/stable/c/5b08dccecf825cbf905f348bc6ccb497507e28e2
https://git.kernel.org/stable/c/5e658b9245a52d838ef93729a7bc07de8e19deb7
https://git.kernel.org/stable/c/e574af95234afc3c725988bbc1fdeb46b9f386a4
https://git.kernel.org/stable/c/e8852ae29868e449fdb47eebc28f35fb80741a5f
https://git.kernel.org/stable/c/f8d420949b335a4b51d06ab276beee6b8dfdc909

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-19 12:16

Updated : 2026-08-17 05:17

NVD link : CVE-2026-63833

Mitre link : CVE-2026-63833

CVE.ORG link : CVE-2026-63833

JSON object : View

Products Affected

No product.

CWE

No CWE.

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