Local system crash via JFS trim race
Published Jul 4, 2025 · Updated Sep 2, 2026
NULL pointer dereference in the Linux kernel JFS module allows local users to crash the system through a crafted trim ioctl race. During concurrent JFS operations, dbFreeBits can clear the superblock bmap pointer while jfs_ioc_trim subsequently dereferences it without synchronization. Reaching the flaw requires local low-privileged ioctl access to a mounted JFS filesystem; successful triggering causes a kernel panic and service interruption.
Summary
What happened
NULL pointer dereference in the Linux kernel JFS module allows local users to crash the system through a crafted trim ioctl race. During concurrent JFS operations, dbFreeBits can clear the superblock bmap pointer while jfs_ioc_trim subsequently dereferences it without synchronization. Reaching the flaw requires local low-privileged ioctl access to a mounted JFS filesystem; successful triggering causes a kernel panic and service interruption.
The record
- CVE
- CVE-2025-38203
- Published
- Jul 4, 2025
- Updated
- Sep 2, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-476, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 4, 2025CVE publishedPublication date reported by the CVE source.
- Sep 2, 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=3.7
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <0d50231d473f89024158dc62624930de45d13718
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <233340626cf1b1887dca181f9f811db60c73f802
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <4a2de0f5b8d7f218bea5bd43d30b466e8b272b8d
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <4a8cb9908b51500a76f5156423bd295df53bff89
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <9806ae34d7d661c372247cd36f83bfa0523d60ed
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <a39f811a9f5edb6d97bede8e6fe730393d3c8537
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <a4685408ff6c3e2af366ad9a7274f45ff3f394ee
- Affected versionversion=b40c2e665cd552eae5fbdbb878bc29a34357668e <a9d41c925069c950e18160e12a7e10e0f58c56fb
What conditions does exploitation require?
What is affected?
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.
Weakness, pattern, technique
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