CVE-2025-22123: Linux kernel · f2fs: fix to avoid accessing uninitialized curseg
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 29 Oct 2026, 23:52 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Apr 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
Users should monitor official Linux kernel advisories for updates addressing this issue. Until a fix is applied, avoid workloads that trigger f2fs no free segment faults. The vendor advisory or kernel release notes should be checked for the official fix.
Description
CVE-2025-22123 is a medium severity vulnerability in the Linux kernel's f2fs filesystem. It involves accessing an uninitialized curseg structure, which can lead to a kernel panic. The issue arises because f2fs_write_inode() does not check the CP_ERROR_FLAG before accessing curseg->segno, potentially causing invalid memory access and system crashes. The flaw was reported by syzbot and fixed by adding proper flag checks and validation of curseg->segno before use.
References
- nvd.nist.gov/vuln/detail/CVE-2025-22123 (opens in a new tab)
- git.kernel.org/stable/c/7f90e5d423cd2d4c74b2abb527872f335108637f (opens in a new tab)
- git.kernel.org/stable/c/986c50f6bca109c6cf362b4e2babcb85aba958f6 (opens in a new tab)
- git.kernel.org/stable/c/bf49527089ec1ba894c6e587affabbfb2329f52e (opens in a new tab)