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CVE-2025-38058

In the Linux kernel, the following vulnerability has been resolved: __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock ...

Published Jun 18, 2025 · updated Oct 15, 2026 · linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock ... or we risk stealing final mntput from sync umount - raising mnt_count after umount(2) has verified that victim is not busy, but before it has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see that it's safe to quietly undo mnt_count increment and leaves dropping the reference to caller, where it'll be a full-blown mntput(). Check under mount_lock is needed; leaving the current one done before taking that makes no sense - it's nowhere near common enough to bother with.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 18, 2025 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock ... or we risk stealing final mntput from sync umount - raising mnt_count after umount(2) has verified that victim is not busy, but before it has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see that it's safe to quietly undo mnt_count increme

  2. Oct 15, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock ... or we risk stealing final mntput from sync umount - raising mnt_count after umount(2) has verified that victim is not busy, but before it has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see that it's safe to quietly undo mnt_count increme

Affected

  • cpe debian/debian linux11.0
  • cpe linux/linux kernelversion unspecified
  • cpe linux/linux kernel6.15

Sources

  • CVE.orgVulnerability recordCVE-2025-38058

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2025-38058

    In the Linux kernel, the following vulnerability has been resolved: __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock ... or we risk stealing final mntput from sync umount - raising mnt_count after umount(2) has verified that victim is not busy, but befor

    nvd.nist.gov

References

CVE-2025-38058 · ZeroDay Findings