CVE-2025-38730 io_uring/net: commit partial buffers on retry
A local attacker can cause memory corruption or denial of service in the Linux kernel by exploiting improper buffer handling in io_uring network operations.
- 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-2025-38730?
CVE-2025-38730 is a high-severity memory corruption vulnerability in Linux kernel, published on 4 Sep 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:
io_uring/net: commit partial buffers on retry
Ring provided buffers are potentially only valid within the single execution context in which they were acquired. io_uring deals with this and invalidates them on retry. But on the networking side, if MSG_WAITALL is set, or if the socket is of the streaming type and too little was processed, then it will hang on to the buffer rather than recycle or commit it. This is problematic for two reasons:
1) If someone unregisters the provided buffer ring before a later retry, then the req->buf_list will no longer be valid.
2) If multiple sockers are using the same buffer group, then multiple receives can consume the same memory. This can cause data corruption in the application, as either receive could land in the same userspace buffer.
Fix this by disallowing partial retries from pinning a provided buffer across multiple executions, if ring provided buffers are used.
Weakness: CWE-787
Which versions are affected by CVE-2025-38730?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-38730?
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-2025-38730 being exploited?
There is no known exploitation of CVE-2025-38730 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-66830, BELL-CVE-2025-38730, DEBIAN-CVE-2025-38730, GHSA-g87f-g973-9jmq, ROOT-OS-UBUNTU-2404-CVE-2025-38730, UBUNTU-CVE-2025-38730.