CVE-2026-74220 U-Boot before 2026.10-rc5 Buffer Overflow via NFS READ Reply
A malicious NFS server can trigger a buffer overflow in U-Boot via crafted READ replies, potentially allowing code execution or crashing the bootloader.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74220?
CVE-2026-74220 is a high-severity memory corruption vulnerability in u-boot, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
U-Boot before 2026.10-rc5 contains a buffer overflow in nfs_read_reply() function in net/nfs-common.c that allows attackers to corrupt memory by supplying crafted NFS READ reply lengths. A malicious NFS server can exploit signed integer handling to bypass length validation and write far past the destination buffer, crashing the bootloader or corrupting memory.
Weakness: CWE-195
Which versions are affected by CVE-2026-74220?
How do I fix CVE-2026-74220?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-74220 being exploited?
There is no known exploitation of CVE-2026-74220 in the wild and no public exploit code.
Sources
Also known as AZL-105699, DEBIAN-CVE-2026-74220, GHSA-63gj-h865-3h3j, UBUNTU-CVE-2026-74220.