{"id":"CVE-2026-63833","summary":"ntfs3: reject direct userspace writes to reserved $LX* xattrs","details":"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]","modified":"2026-07-23T09:59:44.122935321Z","published":"2026-07-19T12:02:25.469Z","related":["openSUSE-SU-2026:11339-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63833.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/293a84fa40b3a1b3471c0545722724bc10973f76"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2c3cd6da4a14380ef79e34bd9dff7caf46687477"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5b08dccecf825cbf905f348bc6ccb497507e28e2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5e658b9245a52d838ef93729a7bc07de8e19deb7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e574af95234afc3c725988bbc1fdeb46b9f386a4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e8852ae29868e449fdb47eebc28f35fb80741a5f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f8d420949b335a4b51d06ab276beee6b8dfdc909"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63833.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63833"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"be71b5cba2e6485e8959da7a9f9a44461a1bb074"},{"fixed":"e574af95234afc3c725988bbc1fdeb46b9f386a4"},{"fixed":"2c3cd6da4a14380ef79e34bd9dff7caf46687477"},{"fixed":"e8852ae29868e449fdb47eebc28f35fb80741a5f"},{"fixed":"f8d420949b335a4b51d06ab276beee6b8dfdc909"},{"fixed":"5e658b9245a52d838ef93729a7bc07de8e19deb7"},{"fixed":"293a84fa40b3a1b3471c0545722724bc10973f76"},{"fixed":"5b08dccecf825cbf905f348bc6ccb497507e28e2"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63833.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.15.0"},{"fixed":"5.15.211"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.177"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.144"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.95"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.38"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63833.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N"}]}