CVE-2026-29009

U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff 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 nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.u-boot-project.org/u-boot/u-boot/-/commit/d6694018eaddefac6aae974f9cec72fd6e58f1bc
https://git.u-boot-project.org/u-boot/u-boot/-/releases/v2026.07-rc2
https://lists.denx.de/pipermail/u-boot/2026-May/617853.html	Mailing List Third Party Advisory
https://u-boot.org/	Product
https://www.vulncheck.com/advisories/u-boot-rc3-buffer-overflow-in-nfs-readlink-reply-via-nfs-readlink	Exploit Third Party Advisory
https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:denx:u-boot::::::::
	cpe:2.3:a:denx:u-boot:2026.04:rc1::::::
	cpe:2.3:a:denx:u-boot:2026.04:rc2::::::
	cpe:2.3:a:denx:u-boot:2026.04:rc3::::::

History

No history.

Information

Published : 2026-07-08 17:17

Updated : 2026-07-24 18:16

NVD link : CVE-2026-29009

Mitre link : CVE-2026-29009

CVE.ORG link : CVE-2026-29009

JSON object : View

Products Affected

denx

u-boot

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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