# CVE-2026-23234: f2fs: fix to avoid UAF in f2fs_write_end_io() CVE-2026-23234 is fixed in 36 products on 1 platform, first by DEBIAN-CVE-2026-23234, released March 4, 2026. It is not reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/cve/CVE-2026-23234 - Priority: High - CVSS: 7.8 (Important) - EPSS: 0.0014 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Mar 4, 2026 - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23234 ## Description 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. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | kernel-uek ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-core ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-core ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-core ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-core ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-devel ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-devel ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-core ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-core ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-deprecated ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-deprecated ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-desktop ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-desktop ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-extra ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-extra ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-extra-netfilter ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-extra-netfilter ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-usb ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-usb ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-wireless ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-debug-modules-wireless ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-devel ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-devel ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-doc ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-doc ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-core ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-core ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-deprecated ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-deprecated ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-desktop ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-desktop ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-extra ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-extra ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-extra-netfilter ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-extra-netfilter ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-usb ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-usb ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-wireless ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-modules-wireless ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-tools ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek-tools ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-core ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-core ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-devel ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-devel ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-core ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-core ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-deprecated ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-deprecated ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-desktop ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-desktop ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-extra ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-extra ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-extra-netfilter ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-extra-netfilter ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-usb ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-usb ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-wireless ol 10 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | kernel-uek64k-modules-wireless ol 9 | 0:6.12.0-200.74.27.el9uek | [ELSA-2026-50160](https://patchblox.com/security/data/fix/linux/elsa-2026-50160.md) | Mar 20, 2026 | | Linux | linux Debian 12.15 (bookworm) | 6.1.164-1 | [DEBIAN-CVE-2026-23234](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23234.md) | Mar 4, 2026 | | Linux | linux Debian 13.5 (trixie) | 6.12.74-2 | [DEBIAN-CVE-2026-23234](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23234.md) | Mar 4, 2026 | | Linux | linux Debian 14 | 6.18.13-1 | [DEBIAN-CVE-2026-23234](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23234.md) | Mar 4, 2026 | --- Data as of 2026-11-09T07:25:28Z UTC. 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