MEDIUM CVSS 5.5
Published: 2026-01-14

CVE-2025-71105

linux linux_kernel Security Advisory (CVE-2025-71105)
↗ Official NIST NVD Record
Seeking technical exploit breakdowns or verified PoC code for CVE-2025-71105?
🔬 Search Writeups & Exploit Archive →

CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2025-71105 impacting linux linux_kernel. Evaluated with CVSS Base Score of 5.5 (MEDIUM).

Original NVD Description

Source: NIST NVD
In the Linux kernel, the following vulnerability has been resolved: f2fs: use global inline_xattr_slab instead of per-sb slab cache As Hong Yun reported in mailing list: loop7: detected capacity change from 0 to 131072 ------------[ cut here ]------------ kmem_cache of name 'f2fs_xattr_entry-7:7' already exists WARNING: CPU: 0 PID: 24426 at mm/slab_common.c:110 kmem_cache_sanity_check mm/slab_common.c:109 [inline] WARNING: CPU: 0 PID: 24426 at mm/slab_common.c:110 __kmem_cache_create_args+0xa6/0x320 mm/slab_common.c:307 CPU: 0 UID: 0 PID: 24426 Comm: syz.7.1370 Not tainted 6.17.0-rc4 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:kmem_cache_sanity_check mm/slab_common.c:109 [inline] RIP: 0010:__kmem_cache_create_args+0xa6/0x320 mm/slab_common.c:307 Call Trace:  __kmem_cache_create include/linux/slab.h:353 [inline]  f2fs_kmem_cache_create fs/f2fs/f2fs.h:2943 [inline]  f2fs_init_xattr_caches+0xa5/0xe0 fs/f2fs/xattr.c:843  f2fs_fill_super+0x1645/0x2620 fs/f2fs/super.c:4918  get_tree_bdev_flags+0x1fb/0x260 fs/super.c:1692  vfs_get_tree+0x43/0x140 fs/super.c:1815  do_new_mount+0x201/0x550 fs/namespace.c:3808  do_mount fs/namespace.c:4136 [inline]  __do_sys_mount fs/namespace.c:4347 [inline]  __se_sys_mount+0x298/0x2f0 fs/namespace.c:4324  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]  do_syscall_64+0x8e/0x3a0 arch/x86/entry/syscall_64.c:94  entry_SYSCALL_64_after_hwframe+0x76/0x7e The bug can be reproduced w/ below scripts: - mount /dev/vdb /mnt1 - mount /dev/vdc /mnt2 - umount /mnt1 - mounnt /dev/vdb /mnt1 The reason is if we created two slab caches, named f2fs_xattr_entry-7:3 and f2fs_xattr_entry-7:7, and they have the same slab size. Actually, slab system will only create one slab cache core structure which has slab name of "f2fs_xattr_entry-7:3", and two slab caches share the same structure and cache address. So, if we destroy f2fs_xattr_entry-7:3 cache w/ cache address, it will decrease reference count of slab cache, rather than release slab cache entirely, since there is one more user has referenced the cache. Then, if we try to create slab cache w/ name "f2fs_xattr_entry-7:3" again, slab system will find that there is existed cache which has the same name and trigger the warning. Let's changes to use global inline_xattr_slab instead of per-sb slab cache for fixing.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Local (AV:L)
Requires local system execution permissions
Attack Complexity
Low (AC:L)
No specialized conditions required
Privileges Required
Low (PR:L)
Standard user access required
User Interaction
None (UI:N)
Zero human interaction required
Scope
Unchanged (S:U)
Confined to same security context
Confidentiality
None (C:N)
No data confidentiality impact
Integrity
None (I:N)
No system modification impact
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product linux / linux_kernel
Affected Versions *
Weakness Enumeration NVD-CWE-noinfo

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2025-71105 impacting linux linux_kernel.

⚡ Nuclei Detection Template (YAML) cve-2025-71105.yaml
id: cve-2025-71105

info:
  name: linux linux_kernel - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2025-71105 affecting linux linux_kernel.
    Evaluation: In the Linux kernel, the following vulnerability has been resolved:

f2fs: use global inline_xattr_slab instead of per-sb slab cache

As Hong Yun repo...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2025-71105
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    cvss-score: 5.5
    cve-id: CVE-2025-71105
    cwe-id: NVD-CWE-noinfo
  tags: cve,cve-2025-71105,linux,linux_kernel,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "linux_kernel"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2025-71105.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2025-71105
# Target: linux linux_kernel | CVSS: 5.5 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2025-71105 (linux linux_kernel)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against linux linux_kernel scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2025-71105.sh
# Recommended Remediation & Patching Commands for CVE-2025-71105
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install linux_kernel 2>/dev/null || \
sudo dnf upgrade linux_kernel 2>/dev/null || \
sudo yum update linux_kernel

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i linux_kernel 2>/dev/null || rpm -qa | grep -i linux_kernel

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2025-71105 in linux linux_kernel?

Review vendor-specific security notices and update linux linux_kernel packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2025-71105?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2025-71105?

CVE-2025-71105 is classified with a CVSS 3.1 Base Score of 5.5 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
5.5
MEDIUM SEVERITY
CVE ID CVE-2025-71105
Weakness NVD-CWE-noinfo
Vendor linux
Product linux_kernel
Published 2026-01-14
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H