{"cve":"CVE-2026-63833","nvd":{"published":"2026-07-19T12:16:56.713","modified":"2026-10-22T14:11:49.023","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs3: reject direct userspace writes to reserved $LX* xattrs\n\nNTFS3 uses $LXUID, $LXGID, $LXMOD and $LXDEV as internal WSL\npermission metadata and reloads them into i_uid, i_gid and i_mode\nfrom ntfs_get_wsl_perm().\n\nBecause the empty-prefix xattr handler also lets file owners call\nsetxattr() on these names directly, an unprivileged writer on a\nwritable ntfs3 mount can plant root ownership and S_ISUID on their own\nfile and gain euid 0 after inode reload.\n\nReject direct userspace writes to the reserved $LX* names. Internal\nntfs3 metadata updates are unchanged because ntfs_save_wsl_perm()\nwrites them via ntfs_set_ea() directly.\n\n[almaz.alexandrovich@paragon-software.com: added an additional check for non privileged users]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","score":7.1},"cwes":["CWE-862"],"references":["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"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-63833","score":0.00144,"percentile":0.0368,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}