DENX U-Boot through 2018.09-rc1 has a remotely exploitable buffer overflow via a malicious TFTP server because TFTP traffic is mishandled. Also, local exploitation can occur via a crafted kernel image.

In Das U-Boot through 2022.07-rc5, an integer signedness error and resultant stack-based buffer overflow in the "i2c md" command enables the corruption of the return address pointer of the doi2cmd function.

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.

In Das U-Boot through 2020.01, a double free has been found in the cmd/gpt.c dorenamegptparts() function. Double freeing may result in a write-what-where condition, allowing an attacker to execute arbitrary code. NOTE: this vulnerablity was introduced when attempting to fix a memory leak identified by static analysis.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy with a failed length check at nfslookupreply.

An issue was discovered in Das U-Boot through 2019.07. There is a stack-based buffer overflow in this nfshandler reply helper function: nfslookupreply.

An issue was discovered in Das U-Boot through 2019.07. There is a stack-based buffer overflow in this nfshandler reply helper function: nfsreadlinkreply.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy with a failed length check at nfsreadreply when calling storeblock in the NFSv2 case.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy when parsing a UDP packet due to a netprocessreceivedpacket integer underflow during an udppackethandler call.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy with a failed length check at nfsreadreply when calling storeblock in the NFSv3 case.

An issue was discovered in Das U-Boot through 2019.07. There is a stack-based buffer overflow in this nfshandler reply helper function: rpclookupreply.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy with an unvalidated length at nfsreadlinkreply, in the "if" block after calculating the new path length.

An issue was discovered in Das U-Boot through 2019.07. There is a stack-based buffer overflow in this nfshandler reply helper function: nfsumountallreply.

An issue was discovered in Das U-Boot through 2019.07. There is a stack-based buffer overflow in this nfshandler reply helper function: nfsmountreply.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy with unvalidated length at nfsreadlinkreply in the "else" block after calculating the new path length.

An issue was discovered in Das U-Boot through 2019.07. There is an unbounded memcpy when parsing a UDP packet due to a netprocessreceivedpacket integer underflow during an ncinputpacket call.

Das U-Boot 2016.11-rc1 through 2019.04 mishandles the ext4 64-bit extension, resulting in a buffer overflow.

nfslookupreply in net/nfs.c in Das U-Boot through 2022.04 (and through 2022.07-rc2) has an unbounded memcpy with a failed length check, leading to a buffer overflow. NOTE: this issue exists because of an incorrect fix for CVE-2019-14196.

An issue was discovered in Das U-Boot through 2019.07. There is a read of out-of-bounds data at nfsreadreply.

Das U-Boot before 2026.04 allows FIT (Flat Image Tree) signature verification bypass because hashed-nodes is omitted from a hash.

U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfsreadlinkreply() (net/nfs-common.c) when CONFIGCMDNFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfspathbuff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfsserverip, nfsservermountport, nfsserverport, nfsourport, nfsstate, and rpcid, potentially achieving memory corruption and control over the NFS client state machine.

U-Boot through 2026.04-rc3 contains an integer underflow vulnerability in the tcprxstatemachine() function (net/tcp.c) that allows a network-adjacent attacker to crash the bootloader by sending a malformed TCP SYN+ACK packet with a manipulated data offset field causing payloadlen to become negative. When the TCPSYNSENT handler calls tcprxuserdata() without invoking tcpseginwnd() validation, the negative payloadlen is implicitly converted to a large unsigned integer (e.g., 0xFFFFFFD8) and passed to memcpy() in storeblock(), causing an immediate crash that prevents device boot and may enable memory corruption when CONFIGLMB is disabled.

Improper access control for volatile memory containing boot code in Universal Boot Loader (U-Boot) before 2017.11 and Qualcomm chips IPQ4019, IPQ5018, IPQ5322, IPQ6018, IPQ8064, IPQ8074, and IPQ9574 could allow an attacker to execute arbitrary code.

barebox is a bootloader. In barebox from version 2016.03.0 to before version 2026.03.1 (and the corresponding backport to 2025.09.3), an attacker could exploit a FIT signature verification vulnerability to trick the bootloader into booting different images than those that were verified as part of a signed configuration. mkimage(1) sets the hashed-nodes property of the FIT signature node to list which nodes of the FIT were hashed as part of the signing process as these will need to be verified later on by the bootloader. However, hashed-nodes itself is not part of the hash and could therefore be modified to allow booting different images than those that have been verified. This issue has been patched in barebox versions 2026.03.1 and backported to 2025.09.3.

An exploitable vulnerability exists in the verified boot protection of the Das U-Boot from version 2013.07-rc1 to 2014.07-rc2. The affected versions lack proper FIT signature enforcement, which allows an attacker to bypass U-Boot's verified boot and execute an unsigned kernel, embedded in a legacy image format. To trigger this vulnerability, a local attacker needs to be able to supply the image to boot.

Buffer Overflow vulnerability in the net/bootp.c in DENEX U-Boot from its initial commit in 2002 (3861aa5) up to today on any platform allows an attacker on the local network to leak memory from four up to 32 bytes of memory stored behind the packet to the network depending on the later use of DHCP-provided parameters via crafted DHCP responses.

Integer overflows in memory allocation in Das U-Boot before 2025.01-rc1 occur for a crafted squashfs filesystem via sbrk, via request2size, or because ptrdifft is mishandled on x8664.

Das U-Boot through 2020.01 allows attackers to bypass verified boot restrictions and subsequently boot arbitrary images by providing a crafted FIT image to a system configured to boot the default configuration.

DENX U-Boot through 2018.09-rc1 has a locally exploitable buffer overflow via a crafted kernel image because filesystem loading is mishandled.

The boot loader in Das U-Boot before 2021.04-rc2 mishandles a modified FIT.