CVE-2023-52983 block, bfq: fix uaf for bfqq in bic_set_bfqq()
A use-after-free flaw in the Linux kernel's BFQ I/O scheduler allows attackers to potentially execute arbitrary code or escalate privileges.
- 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-2023-52983?
CVE-2023-52983 is a high-severity use after free vulnerability in Linux kernel, published on 27 Mar 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:
block, bfq: fix uaf for bfqq in bic_set_bfqq()
After commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'"), bic->bfqq will be accessed in bic_set_bfqq(), however, in some context bic->bfqq will be freed, and bic_set_bfqq() is called with the freed bic->bfqq.
Fix the problem by always freeing bfqq after bic_set_bfqq().
Weakness: CWE-416
Which versions are affected by CVE-2023-52983?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-52983?
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-2023-52983 being exploited?
There is no known exploitation of CVE-2023-52983 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2023-52983, GHSA-2q9r-f82f-3g5x, UBUNTU-CVE-2023-52983.