U-Boot before 2026.10-rc5 contains a buffer overflow in nfs_readlink_reply() function in net/nfs-common.c when processing NFS server responses. A malicious NFS server can send crafted READLINK replies with negative or oversized symlink length values to corrupt memory and crash the bootloader.
https://www.vulncheck.com/advisories/u-boot-before-2026.10-rc5-buffer-overflow-via-nfs-readlink
https://github.com/u-boot/u-boot/commit/1c0aff3a5fbfeee7a8948f624e0b8554e6e0d8fd
https://github.com/u-boot/u-boot/blob/v2026.07/net/nfs-common.c#L643
Published: 2026-09-29
Updated: 2026-09-30
Base Score: 8.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:C
Severity: High
Base Score: 8.2
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Severity: High
Base Score: 8.8
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00344