CVE-2025-39998 scsi: target: target_core_configfs: Add length check to avoid buffer overflow
A buffer overflow in the Linux kernel SCSI target subsystem allows attackers to cause a crash or potentially execute code via crafted input.
- 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-2025-39998?
CVE-2025-39998 is a high-severity memory corruption vulnerability in Linux, published on 15 Oct 2025. 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:
scsi: target: target_core_configfs: Add length check to avoid buffer overflow
A buffer overflow arises from the usage of snprintf to write into the buffer "buf" in target_lu_gp_members_show function located in /drivers/target/target_core_configfs.c. This buffer is allocated with size LU_GROUP_NAME_BUF (256 bytes).
snprintf(...) formats multiple strings into buf with the HBA name (hba->hba_group.cg_item), a slash character, a devicename (dev-> dev_group.cg_item) and a newline character, the total formatted string length may exceed the buffer size of 256 bytes.
Since snprintf() returns the total number of bytes that would have been written (the length of %s/%sn ), this value may exceed the buffer length (256 bytes) passed to memcpy(), this will ultimately cause function memcpy reporting a buffer overflow error.
An additional check of the return value of snprintf() can avoid this buffer overflow.
Which versions are affected by CVE-2025-39998?
How do I fix CVE-2025-39998?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-39998 being exploited?
There is no known exploitation of CVE-2025-39998 in the wild and no public exploit code.
Sources
Also known as AZL-68504, BELL-CVE-2025-39998, DEBIAN-CVE-2025-39998, GHSA-h5vm-jvgf-qf7m, ROOT-OS-DEBIAN-11-CVE-2025-39998, ROOT-OS-DEBIAN-12-CVE-2025-39998 and 4 more.