Vulnerability Database

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Total vulnerabilities in the database

CVE-2026-23201 — linux / linux_kernel

NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved:

ceph: fix oops due to invalid pointer for kfree() in parse_longname()

This fixes a kernel oops when reading ceph snapshot directories (.snap), for example by simply running ls /mnt/my_ceph/.snap.

The variable str is guarded by __free(kfree), but advanced by one for skipping the initial '_' in snapshot names. Thus, kfree() is called with an invalid pointer. This patch removes the need for advancing the pointer so kfree() is called with correct memory pointer.

Steps to reproduce:

  1. Create snapshots on a cephfs volume (I've 63 snaps in my testcase)

  2. Add cephfs mount to fstab $ echo "[email protected]=/volumes/datapool/stuff/3461082b-ecc9-4e82-8549-3fd2590d3fb6 /mnt/test/stuff ceph acl,noatime,_netdev 0 0" >> /etc/fstab

  3. Reboot the system $ systemctl reboot

  4. Check if it's really mounted $ mount | grep stuff

  5. List snapshots (expected 63 snapshots on my system) $ ls /mnt/test/stuff/.snap

Now ls hangs forever and the kernel log shows the oops.

  • Published: Feb 14, 2026
  • Updated: Mar 20, 2026
  • CVE: CVE-2026-23201
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.5
  • AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CWEs:

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