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PatchSiren cyber security CVE debrief

CVE-2026-63793 Linux CVE debrief

A use-after-free vulnerability in the Linux kernel's NTFS subsystem has been resolved. The vulnerability occurred when the FS_IOC_SETFSLABEL and FS_IOC_GETTSLABEL operations were executed concurrently, leading to a potential use-after-free issue. The fix involves protecting the vol->volume_label with a mutex and snapshotting the label before copy_to_user. This vulnerability affected the Linux kernel's NTFS subsystem, and its resolution involves protecting the vol->volume_label with a mutex.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-19
Original CVE updated
2026-07-20
Advisory published
2026-07-19
Advisory updated
2026-07-20

Who should care

Linux kernel developers and maintainers, as well as users of Linux-based systems, should be aware of this vulnerability and ensure that their systems are updated with the patched kernel. They should review the official advisory for affected scope and severity, and apply kernel patches accordingly.

Technical summary

The Linux kernel's NTFS subsystem had a use-after-free vulnerability. When FS_IOC_SETFSLABEL replaced the vol->volume_label and FS_IOC_GETTSLABEL read it concurrently, a use-after-free occurred. The fix protects vol->volume_label with a mutex and snapshots the label before copy_to_user. This vulnerability affected the Linux kernel's NTFS subsystem, and its resolution involves protecting the vol->volume_label with a mutex.

Defensive priority

Medium

Recommended defensive actions

  • Update Linux kernel to the latest version
  • Review and apply kernel patches
  • Monitor system logs for suspicious activity
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record was published on 2026-07-19T12:16:51.650Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the official advisory.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-19T12:16:51.650Z and has not been modified since then.