Vulnerability Database

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Total vulnerabilities in the database

CVE-2025-71107 — linux / linux_kernel

NULL Pointer Dereference

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

f2fs: ensure node page reads complete before f2fs_put_super() finishes

Xfstests generic/335, generic/336 sometimes crash with the following message:

F2FS-fs (dm-0): detect filesystem reference count leak during umount, type: 9, count: 1 ------------[ cut here ]------------ kernel BUG at fs/f2fs/super.c:1939! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 609351 Comm: umount Tainted: G W 6.17.0-rc5-xfstests-g9dd1835ecda5 #1 PREEMPT(none) Tainted: [W]=WARN Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:f2fs_put_super+0x3b3/0x3c0 Call Trace: <TASK> generic_shutdown_super+0x7e/0x190 kill_block_super+0x1a/0x40 kill_f2fs_super+0x9d/0x190 deactivate_locked_super+0x30/0xb0 cleanup_mnt+0xba/0x150 task_work_run+0x5c/0xa0 exit_to_user_mode_loop+0xb7/0xc0 do_syscall_64+0x1ae/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> ---[ end trace 0000000000000000 ]---

It appears that sometimes it is possible that f2fs_put_super() is called before all node page reads are completed. Adding a call to f2fs_wait_on_all_pages() for F2FS_RD_NODE fixes the problem.

  • Published: Jan 14, 2026
  • Updated: Mar 26, 2026
  • CVE: CVE-2025-71107
  • 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:

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

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Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

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