Linux Kernel up to 6.16.0 f2fs f2fs_inode_info use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.16.0 and classified as critical. This vulnerability affects the function f2fs_inode_info of the component f2fs. Performing a manipulation results in use after free. This vulnerability was named CVE-2025-38627. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.16.0. This affects the function f2fs_inode_info of the component f2fs. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: f2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic The decompress_io_ctx may be released asynchronously after I/O completion. If this file is deleted immediately after read, and the kworker of processing post_read_wq has not been executed yet due to high workloads, It is possible that the inode(f2fs_inode_info) is evicted and freed before it is used f2fs_free_dic. The UAF case as below: Thread A Thread B - f2fs_decompress_end_io - f2fs_put_dic - queue_work add free_dic work to post_read_wq - do_unlink - iput - evict - call_rcu This file is deleted after read. Thread C kworker to process post_read_wq - rcu_do_batch - f2fs_free_inode - kmem_cache_free inode is freed by rcu - process_scheduled_works - f2fs_late_free_dic - f2fs_free_dic - f2fs_release_decomp_mem read (dic->inode)->i_compress_algorithm This patch store compress_algorithm and sbi in dic to avoid inode UAF. In addition, the previous solution is deprecated in [1] may cause system hang. [1] https://lore.kernel.org/all/[email protected]

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-38627 since 04/16/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/28/2026).

The vulnerability scanner Nessus provides a plugin with the ID 302764 (Ubuntu 22.04 LTS / 24.04 LTS : Linux kernel vulnerabilities (USN-8095-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.16.1 or 6.17-rc1 eliminates this vulnerability. Applying the patch 8fae5b6addd5f6895e03797b56e3c7b9f9cd15c9/39868685c2a94a70762bc6d77dc81d781d05bff5 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (302764) and CERT Bund (WID-SEC-2025-1898). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • NetApp AFF
  • NetApp ActiveIQ Unified Manager
  • SUSE openSUSE
  • Dell Avamar
  • NetApp FAS
  • Open Source Linux Kernel
  • Dell NetWorker
  • Dell Secure Connect Gateway
  • Dell ECS

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 302764
Nessus Name: Ubuntu 22.04 LTS / 24.04 LTS : Linux kernel vulnerabilities (USN-8095-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.16.1/6.17-rc1
Patch: 8fae5b6addd5f6895e03797b56e3c7b9f9cd15c9/39868685c2a94a70762bc6d77dc81d781d05bff5

Timelineinfo

04/16/2025 CVE reserved
08/22/2025 +128 days Advisory disclosed
08/22/2025 +0 days VulDB entry created
05/28/2026 +279 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38627 (🔒)
GCVE (CVE): GCVE-0-2025-38627
GCVE (VulDB): GCVE-100-321093
CERT Bund: WID-SEC-2025-1898 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service und Privilegieneskalation

Entryinfo

Created: 08/22/2025 23:32
Updated: 05/28/2026 16:57
Changes: 08/22/2025 23:32 (59), 09/22/2025 00:40 (7), 09/23/2025 16:01 (1), 10/17/2025 21:47 (1), 10/26/2025 08:31 (1), 11/26/2025 20:55 (12), 12/13/2025 04:47 (1), 02/13/2026 19:54 (1), 03/18/2026 19:02 (2), 05/28/2026 16:57 (3)
Complete: 🔍
Cache ID: 216::103

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