Kernel panic via invalid F2FS segment access
Published Apr 16, 2025 · Updated May 11, 2026
Denial of service in F2FS in Linux kernel 6.9 allows local users to trigger a kernel panic after a no-free-segment fault. After the allocator records NULL_SEGNO and sets CP_ERROR_FLAG, f2fs_write_inode() omits the flag check and get_ckpt_valid_blocks() dereferences the invalid curseg->segno value. Local low-privileged access to an F2FS filesystem and a no-free-segment condition are required; the documented consequence is availability loss only.
Summary
What happened
Denial of service in F2FS in Linux kernel 6.9 allows local users to trigger a kernel panic after a no-free-segment fault. After the allocator records NULL_SEGNO and sets CP_ERROR_FLAG, f2fs_write_inode() omits the flag check and get_ckpt_valid_blocks() dereferences the invalid curseg->segno value. Local low-privileged access to an F2FS filesystem and a no-free-segment condition are required; the documented consequence is availability loss only.
The record
- CVE
- CVE-2025-22123
- Published
- Apr 16, 2025
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-908, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 16, 2025CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=6.9
- Affected versionversion=8b10d3653735e117bc1954ade80d75ad7b46b801 <7f90e5d423cd2d4c74b2abb527872f335108637f
- Affected versionversion=8b10d3653735e117bc1954ade80d75ad7b46b801 <986c50f6bca109c6cf362b4e2babcb85aba958f6
- Affected versionversion=8b10d3653735e117bc1954ade80d75ad7b46b801 <bf49527089ec1ba894c6e587affabbfb2329f52e
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo