Summary
In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Keep write...
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Keep write operations atomic
syzbot reported a NULL pointer dereference in __generic_file_write_iter. [1]
Before the write operation is completed, the user executes ioctl[2] to clear
the compress flag of the file, which causes the is_compressed() judgment to
return 0, further causing the program to enter the wrong process and call the
wrong ops ntfs_aops_cmpr, which triggers the null pointer dereference of
write_begin.
Use inode lock to synchronize ioctl and write to avoid this case.
[1]
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000086000006
EC = 0x21: IABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=000000011896d000
[0000000000000000] pgd=0800000118b44403, p4d=0800000118b44403, pud=0800000117517403, pmd=0000000000000000
Internal error: Oops: 0000000086000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6427 Comm: syz-executor347 Not tainted 6.13.0-rc3-syzkaller-g573067a5a685 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : generic_perform_write+0x29c/0x868 mm/filemap.c:4055
sp : ffff80009d4978a0
x29: ffff80009d4979c0 x28: dfff800000000000 x27: ffff80009d497bc8
x26: 0000000000000000 x25: ffff80009d497960 x24: ffff80008ba71c68
x23: 0000000000000000 x22: ffff0000c655dac0 x21: 0000000000001000
x20: 000000000000000c x19: 1ffff00013a92f2c x18: ffff0000e183aa1c
x17: 0004060000000014 x16: ffff800083275834 x15: 0000000000000001
x14: 0000000000000000 x13: 0000000000000001 x12: ffff0000c655dac0
x11: 0000000000ff0100 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff80009d497980 x4 : ffff80009d497960 x3 : 0000000000001000
x2 : 0000000000000000 x1 : ffff0000e183a928 x0 : ffff0000d60b0fc0
Call trace:
0x0 (P)
__generic_file_write_iter+0xfc/0x204 mm/filemap.c:4156
ntfs_file_write_iter+0x54c/0x630 fs/ntfs3/file.c:1267
new_sync_write fs/read_write.c:586 [inline]
vfs_write+0x920/0xcf4 fs/read_write.c:679
ksys_write+0x15c/0x26c fs/read_write.c:731
__do_sys_write fs/read_write.c:742 [inline]
__se_sys_write fs/read_write.c:739 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:739
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
[2]
ioctl$FS_IOC_SETFLAGS(r0, 0x40086602, &(0x7f00000000c0)=0x20)
Impact
The application dereferences a null pointer, causing a crash. Typical impact: denial of service via crash.
CVE-2025-37806 has a CVSS score of 5.5 (Medium). The vector is requires local access, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Frequently Asked Questions
- What is CVE-2025-37806? CVE-2025-37806 is a medium-severity null pointer dereference vulnerability. No fixed version is listed yet. The application dereferences a null pointer, causing a crash.
- How severe is CVE-2025-37806? CVE-2025-37806 has a CVSS score of 5.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Is there a fix for CVE-2025-37806? No fixed version is listed for CVE-2025-37806 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-37806 exploitable, and should I be worried? Whether CVE-2025-37806 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-37806 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.