CVE-2025-71312 fs/ntfs3: fix ntfs_mount_options leak in ntfs_fill_super()
A memory leak in the Linux kernel NTFS3 driver allows local attackers to exhaust kernel memory by repeatedly mounting filesystems, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-71312?
CVE-2025-71312 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: fix ntfs_mount_options leak in ntfs_fill_super()
In ntfs_fill_super(), the fc->fs_private pointer is set to NULL without first freeing the memory it points to. This causes the subsequent call to ntfs_fs_free() to skip freeing the ntfs_mount_options structure.
This results in a kmemleak report:
unreferenced object 0xff1100015378b800 (size 32): comm "mount", pid 582, jiffies 4294890685 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 ed ff ed ff 00 04 00 00 ................ backtrace (crc ed541d8c): __kmalloc_cache_noprof+0x424/0x5a0 __ntfs_init_fs_context+0x47/0x590 alloc_fs_context+0x5d8/0x960 __x64_sys_fsopen+0xb1/0x190 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e
This issue can be reproduced using the following commands: fallocate -l 100M test.file mount test.file /tmp/test
Since sbi->options is duplicated from fc->fs_private and does not directly use the memory allocated for fs_private, it is unnecessary to set fc->fs_private to NULL.
Additionally, this patch simplifies the code by utilizing the helper function put_mount_options() instead of open-coding the cleanup logic.
Weakness: CWE-401
Which versions are affected by CVE-2025-71312?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-71312?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-71312 being exploited?
There is no known exploitation of CVE-2025-71312 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as GHSA-w58m-8mj8-hh8w, UBUNTU-CVE-2025-71312.