CVE-2025-37823 net_sched: hfsc: Fix a potential UAF in hfsc_dequeue() too
A use-after-free vulnerability in the Linux kernel's HFSC network scheduler allows attackers to potentially execute 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-2025-37823?
CVE-2025-37823 is a high-severity use after free vulnerability in Debian Debian Linux, published on 8 May 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:
net_sched: hfsc: Fix a potential UAF in hfsc_dequeue() too
Similarly to the previous patch, we need to safe guard hfsc_dequeue() too. But for this one, we don't have a reliable reproducer.
Weakness: CWE-416
Which versions are affected by CVE-2025-37823?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2025-37823?
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-2025-37823 being exploited?
There is no known exploitation of CVE-2025-37823 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as BELL-CVE-2025-37823, DEBIAN-CVE-2025-37823, GHSA-gr82-7xxj-rqx8, ROOT-OS-DEBIAN-12-CVE-2025-37823, ROOT-OS-UBUNTU-2204-CVE-2025-37823, ROOT-OS-UBUNTU-2404-CVE-2025-37823 and 1 more.