CVE-2025-38571 sunrpc: fix client side handling of tls alerts
A null pointer dereference in the Linux kernel's NFS over TLS client allows attackers to cause a denial of service via crafted TLS alerts.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-38571?
CVE-2025-38571 is a high-severity vulnerability in Linux kernel, published on 19 Aug 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
sunrpc: fix client side handling of tls alerts
A security exploit was discovered in NFS over TLS in tls_alert_recv due to its assumption that there is valid data in the msghdr's iterator's kvec.
Instead, this patch proposes the rework how control messages are setup and used by sock_recvmsg().
If no control message structure is setup, kTLS layer will read and process TLS data record types. As soon as it encounters a TLS control message, it would return an error. At that point, NFS can setup a kvec backed control buffer and read in the control message such as a TLS alert. Scott found that a msg iterator can advance the kvec pointer as a part of the copy process thus we need to revert the iterator before calling into the tls_alert_recv.
Which versions are affected by CVE-2025-38571?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-38571?
Apply the vendor's patch.
Is CVE-2025-38571 being exploited?
There is no known exploitation of CVE-2025-38571 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-66467, BELL-CVE-2025-38571, DEBIAN-CVE-2025-38571, GHSA-r3wq-5xjj-hj39, ROOT-OS-DEBIAN-13-CVE-2025-38571, ROOT-OS-UBUNTU-2404-CVE-2025-38571 and 1 more.