Back to CVE records
Medium 5.5Published Jul 25, 2026

CVE-2026-64417In the Linux kernel, the following vulnerability has been resolved: mm: shrinker: fix NULL pointer dereference in debugfs shrinker_debugfs_add() creates both "count" and "scan" debugfs files uncondit…

Updated under an hour ago ()

Does this affect you?

It affects linux_kernel. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

In the Linux kernel, the following vulnerability has been resolved: mm: shrinker: fix NULL pointer dereference in debugfs shrinker_debugfs_add() creates both "count" and "scan" debugfs files unconditionally. That assumes every shrinker implements both count_objects() and scan_objects(), which is not guaranteed. For example, the xen-backend shrinker sets count_objects() but leaves scan_objects() NULL, so writing to its scan file calls through a NULL function pointer and panics the kernel: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. Call Trace: <TASK> shrinker_debugfs_scan_write+0x12e/0x270 full_proxy_write+0x5f/0x90 vfs_write+0xde/0x420 ? filp_flush+0x75/0x90 ? filp_close+0x1d/0x30 ? do_dup2+0xb8/0x120 ksys_write+0x68/0xf0 ? filp_flush+0x75/0x90 do_syscall_64+0xb3/0x5b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The count path has the same issue in principle if a shrinker omits count_objects(). To fix it, only create "count" and "scan" debugfs files when the corresponding callbacks are present.

CVSS
5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-476
Known exploited
Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days)
Not loaded for this CVE
Assigned by
Not given
NVD analysis
Analyzed
Record last updated
Sep 4, 2026
First seen by InfoSec Signals
Oct 9, 2026

Affected products

Affected products
linux linux_kernel
linux:linux_kernel
from 6.0 before 6.1.178; from 6.2 before 6.6.145; from 6.7 before 6.12.96; from 6.13 before 6.18.39; from 6.19 before 7.1.4; 7.2; 7.2
NVD

References

  • patch
  • patch
  • patch
  • patch
  • patch
  • patch

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.

Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.