CVE-2025-40062 crypto: hisilicon/qm - set NULL to qm->debug.qm_diff_regs
A double free vulnerability in the Linux kernel Hisilicon QM driver can cause a system crash during device removal if initialization fails.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-40062?
CVE-2025-40062 is an use after free vulnerability in Linux, published on 28 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:
crypto: hisilicon/qm - set NULL to qm->debug.qm_diff_regs
When the initialization of qm->debug.acc_diff_reg fails, the probe process does not exit. However, after qm->debug.qm_diff_regs is freed, it is not set to NULL. This can lead to a double free when the remove process attempts to free it again. Therefore, qm->debug.qm_diff_regs should be set to NULL after it is freed.
Which versions are affected by CVE-2025-40062?
How do I fix CVE-2025-40062?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2025-40062 being exploited?
There is no known exploitation of CVE-2025-40062 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-40062, DEBIAN-CVE-2025-40062, GHSA-8c8f-r28v-v5hp, ROOT-OS-DEBIAN-12-CVE-2025-40062, ROOT-OS-DEBIAN-13-CVE-2025-40062, ROOT-OS-UBUNTU-2404-CVE-2025-40062 and 1 more.