{"id":"CVE-2026-63793","state":"PUBLISHED","title":"ntfs: serialize volume label accesses","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: serialize volume label accesses\n\nProtect vol->volume_label with a mutex and snaphost the label before\ncopy_to_user. This prevent a use-after-free when FS_IOC_SETFSLABEL\nreplaces the vol->volume_label and FS_IOC_GETTSLABEL reads it\nconcurrently.","publishedAt":"2026-07-19T12:02:02.946Z","updatedAt":"2026-08-17T04:50:57.837Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9c87959601e80b39a45250e362e6ddfec17cb0fa","status":"affected","lessThan":"acd744019460bad22e43d4569a502f9c88d331ae","versionType":"git"},{"version":"9c87959601e80b39a45250e362e6ddfec17cb0fa","status":"affected","lessThan":"e9e50ce4f13dc721014af622613409455c734942","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/file.c","fs/ntfs/super.c","fs/ntfs/volume.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.1","versionType":"semver"},{"version":"7.1.3","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/file.c","fs/ntfs/super.c","fs/ntfs/volume.h"]}],"references":["https://git.kernel.org/stable/c/acd744019460bad22e43d4569a502f9c88d331ae","https://git.kernel.org/stable/c/e9e50ce4f13dc721014af622613409455c734942"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/63xxx/CVE-2026-63793.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63793","state":"PUBLISHED","datePublished":"2026-07-19T12:02:02.946Z","dateUpdated":"2026-08-17T04:50:57.837Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T07:54:57.012Z"},"containers":{"cna":{"title":"ntfs: serialize volume label accesses","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: serialize volume label accesses\n\nProtect vol->volume_label with a mutex and snaphost the label before\ncopy_to_user. This prevent a use-after-free when FS_IOC_SETFSLABEL\nreplaces the vol->volume_label and FS_IOC_GETTSLABEL reads it\nconcurrently."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9c87959601e80b39a45250e362e6ddfec17cb0fa","status":"affected","lessThan":"acd744019460bad22e43d4569a502f9c88d331ae","versionType":"git"},{"version":"9c87959601e80b39a45250e362e6ddfec17cb0fa","status":"affected","lessThan":"e9e50ce4f13dc721014af622613409455c734942","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/file.c","fs/ntfs/super.c","fs/ntfs/volume.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.1","versionType":"semver"},{"version":"7.1.3","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/file.c","fs/ntfs/super.c","fs/ntfs/volume.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/acd744019460bad22e43d4569a502f9c88d331ae"},{"url":"https://git.kernel.org/stable/c/e9e50ce4f13dc721014af622613409455c734942"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerability is reached only through the local ioctl(2) syscall on an open file or directory on a mounted legacy NTFS (fs/ntfs) volume; there is no network-facing code path to these handlers.\nAC:L - An attacker controls both sides of the race by concurrently issuing FS_IOC_SETFSLABEL and FS_IOC_GETFSLABEL from separate threads or file descriptors, making the use-after-free reliably triggerable without conditions outside attacker control.\nPR:L - Exploitation requires CAP_SYS_ADMIN to call FS_IOC_SETFSLABEL (which performs the kfree), but that capability is obtainable by an unprivileged user via user namespaces or privileged containers, and mounting NTFS for ioctl access does not require init-namespace root.\nUI:N - No victim interaction is required; the attacker opens a file on the NTFS mount and races the label get/set ioctls themselves, including on auto-mounted dual-boot or shared-workstation NTFS partitions.\nS:U - The use-after-free corrupts kernel heap memory within the same kernel security authority and does not cross VM, container, or IOMMU boundaries on its own.\nC:H - The bug is a kmalloc use-after-free where the read path calls strlen() and copy_to_user() on freed memory, enabling disclosure of adjacent heap contents to userspace and supporting further info-leak primitives.\nI:H - Use-after-free on a kmalloc-allocated volume label string is a standard heap corruption primitive that can be groomed for arbitrary kernel memory writes and potential privilege escalation or code execution.\nA:H - Concurrent access to the freed label pointer can cause kernel oopses or panics during strlen() or copy_to_user(), and UAF corruption inherently threatens system availability even before full exploitation."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:50:57.837Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.1.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}