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7.8
HIGH CVSS 3.1
CVE-2025-21879
"btrfs Use-After-Free Vulnerability"
Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free on inode when scanning root during em shrinking At btrfs_scan_root() we are accessing the inode's root (and fs_info) in a call to btrfs_fs_closing() after we have scheduled the inode for a delayed iput, and that can result in a use-after-free on the inode in case the cleaner kthread does the iput before we dereference the inode in the call to btrfs_fs_closing(). Fix this by using the fs_info stored already in a local variable instead of doing inode->root->fs_info.

INFO

Published Date :

March 27, 2025, 3:15 p.m.

Last Modified :

July 6, 2025, 10:15 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2025-21879 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
Patch the Linux kernel to resolve a use-after-free vulnerability in btrfs.
  • Update the Linux kernel to the latest stable version.
  • Apply the specific btrfs patch to the kernel source.
  • Recompile and install the modified kernel.
  • Reboot the system to load the updated kernel.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-21879.

URL Resource
https://git.kernel.org/stable/c/07836bc18f4ae42da4e922244f4685561c18755e
https://git.kernel.org/stable/c/59f37036bb7ab3d554c24abc856aabca01126414 Patch
https://git.kernel.org/stable/c/5e79d26014f9386387575b9ed60d342057cee49b Patch
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-21879 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-21879 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-21879 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2025-21879 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 06, 2025

    Action Type Old Value New Value
    Added Reference https://git.kernel.org/stable/c/07836bc18f4ae42da4e922244f4685561c18755e
  • Initial Analysis by [email protected]

    Apr. 01, 2025

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.13.6 *cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/59f37036bb7ab3d554c24abc856aabca01126414 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/5e79d26014f9386387575b9ed60d342057cee49b Types: Patch
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Mar. 28, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-416
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Mar. 27, 2025

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free on inode when scanning root during em shrinking At btrfs_scan_root() we are accessing the inode's root (and fs_info) in a call to btrfs_fs_closing() after we have scheduled the inode for a delayed iput, and that can result in a use-after-free on the inode in case the cleaner kthread does the iput before we dereference the inode in the call to btrfs_fs_closing(). Fix this by using the fs_info stored already in a local variable instead of doing inode->root->fs_info.
    Added Reference https://git.kernel.org/stable/c/59f37036bb7ab3d554c24abc856aabca01126414
    Added Reference https://git.kernel.org/stable/c/5e79d26014f9386387575b9ed60d342057cee49b
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact