CVE-2026-74221

U-Boot before 2026.10-rc5 contains a buffer overflow in the 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.

U-Boot through 2026.10-rc5 contains an out-of-bounds write vulnerability in the video_display_rle8_bitmap function in drivers/video/video_bmp.c. An attacker can supply a crafted RLE8-compressed BMP image to corrupt memory adjacent to the framebuffer and crash the bootloader.

U-Boot before 2026.10-rc3 with CONFIG_IP_DEFRAG enabled contains an out-of-bounds write vulnerability in the __net_defragment() function in net/net.c. Remote attackers can send a crafted IP fragment with non-zero offset and More-Fragments flag set during netboot to corrupt adjacent memory and crash the bootloader.

There exists an unchecked length field in U-Boot that can lead to memory corruption. The DFU implementation in U-Boot does not bound the length field in USB DFU download setup packets, allowing an attacker to send a packet with a length greater than 4096 bytes.

An issue was discovered in Denx U-Boot before 2026.04. An integer overflow vulnerability exists in function ext4fs_get_bgdtable, the size calculation can lead to under allocation and this underallocated buffer will be used in memcpy() which could lead to arbitrary code execution, a denial of service, or other unspecified impacts.

An issue was discovered in Denx U-Boot before 2026.04. An integer overflow vulnerability in the ZFS filesystem support can be triggered by malformed on-disk metadata. The issue may result in incorrect memory allocation followed by out-of-bounds memory access, potentially leading to a crash or arbitrary code execution during the boot process.

U-Boot before 2026.10-rc5 contains an out-of-bounds memory access in dhcp6_parse_options() that fails to validate SERVERID and CLIENTID option lengths from DHCPv6 packets. Attackers on the local network can send crafted DHCPv6 ADVERTISE or REPLY packets during netboot to corrupt memory and crash the bootloader.

U-Boot before 2026.10-rc5 contains a use-after-free vulnerability in the httpc_recv_cb() function within the lwIP wget implementation. When HTTP data storage fails, the callback frees the connection PCB but returns ERR_BUF instead of ERR_ABRT, causing the TCP input path to access released memory and crash the bootloader.

U-Boot before 2026.10-rc3 contains an out-of-bounds write vulnerability in read_slotted_partition() that fails to validate image size against partition bounds. An attacker with physical access can supply crafted boot media with oversized headers to write past the load buffer into bootloader memory on devices without Android Verified Boot protection.

U-Boot before 2026.10-rc4 contains an integer overflow vulnerability in sqfs_read_directory_table() when allocating the directory table buffer. An attacker can supply a crafted SquashFS image with an attacker-controlled superblock metablks_count value that causes heap buffer under-allocation and out-of-bounds writes, corrupting heap memory and crashing the bootloader.