Linux Kernel up to 6.19.2 f2fs f2fs_write_end_io 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, which was classified as critical, was found in Linux Kernel up to 6.19.2. The affected element is the function f2fs_write_end_io of the component f2fs. Such manipulation leads to use after free. This vulnerability is listed as CVE-2026-23234. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.19.2 and classified as critical. Affected by this issue is the function f2fs_write_end_io of the component f2fs. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid UAF in f2fs_write_end_io() As syzbot reported an use-after-free issue in f2fs_write_end_io(). It is caused by below race condition: loop device umount - worker_thread - loop_process_work - do_req_filebacked - lo_rw_aio - lo_rw_aio_complete - blk_mq_end_request - blk_update_request - f2fs_write_end_io - dec_page_count - folio_end_writeback - kill_f2fs_super - kill_block_super - f2fs_put_super : free(sbi) : get_pages(, F2FS_WB_CP_DATA) accessed sbi which is freed In kill_f2fs_super(), we will drop all page caches of f2fs inodes before call free(sbi), it guarantee that all folios should end its writeback, so it should be safe to access sbi before last folio_end_writeback(). Let's relocate ckpt thread wakeup flow before folio_end_writeback() to resolve this issue.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-23234 since 01/13/2026. The exploitation is known to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/24/2026).

The vulnerability scanner Nessus provides a plugin with the ID 301079 (Linux Distros Unpatched Vulnerability : CVE-2026-23234), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.251, 5.15.201, 6.1.164, 6.6.127, 6.12.74, 6.18.13, 6.19.3 or 7.0-rc1 eliminates this vulnerability. Applying the patch 0fb58aff0dafd6837cc91f4154f3ed6e020358fa/2f67ff1e15a8a4d0e4ffc6564ab20d03d7398fe9/505e1c0530db6152cab3feef8e3e4da3d3e358c9/acc2c97fc0005846e5cf11b5ba3189fef130c9b3/cf4a9e1bc8129eb63fda5f8bdcd8d87f0bd76f42/995030be4ce6338c6ff814583c14166446a64008/a42f99be8a16b32a0bb91bb6dda212a6ad61be5d/ce2739e482bce8d2c014d76c4531c877f382aa54 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 (301079) and CERT Bund (WID-SEC-2026-0614). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Microsoft Azure Linux
  • Open Source Linux Kernel
  • IBM QRadar SIEM

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: 301079
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-23234

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.251/5.15.201/6.1.164/6.6.127/6.12.74/6.18.13/6.19.3/7.0-rc1
Patch: 0fb58aff0dafd6837cc91f4154f3ed6e020358fa/2f67ff1e15a8a4d0e4ffc6564ab20d03d7398fe9/505e1c0530db6152cab3feef8e3e4da3d3e358c9/acc2c97fc0005846e5cf11b5ba3189fef130c9b3/cf4a9e1bc8129eb63fda5f8bdcd8d87f0bd76f42/995030be4ce6338c6ff814583c14166446a64008/a42f99be8a16b32a0bb91bb6dda212a6ad61be5d/ce2739e482bce8d2c014d76c4531c877f382aa54

Timelineinfo

01/13/2026 CVE reserved
03/04/2026 +50 days Advisory disclosed
03/04/2026 +0 days VulDB entry created
06/24/2026 +112 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23234 (🔒)
GCVE (CVE): GCVE-0-2026-23234
GCVE (VulDB): GCVE-100-348728
CERT Bund: WID-SEC-2026-0614 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 03/04/2026 16:06
Updated: 06/24/2026 07:50
Changes: 03/04/2026 16:06 (59), 03/05/2026 13:23 (7), 03/07/2026 22:18 (2), 03/18/2026 06:43 (12), 04/20/2026 11:35 (1), 04/29/2026 22:59 (1), 06/24/2026 07:50 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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