Critical severity · published Jul 8, 2026
CVE-2026-29009
U-Boot < 2026.07-rc2 Buffer Overflow in nfs_readlink_reply() via NFS READLINK
9.8
CVSS
0.7%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UB
u-boot · u-boot
before 2026.07-rc2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-29009
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-29009
git.u-boot-project.org
https://git.u-boot-project.org/u-boot/u-boot/-/commit/d6694018eaddefac6aae974f9cec72fd6e58f1bc
git.u-boot-project.org
https://git.u-boot-project.org/u-boot/u-boot/-/releases/v2026.07-rc2
Mailing List
https://lists.denx.de/pipermail/u-boot/2026-May/617853.html
Product
https://u-boot.org/
Exploit
https://www.vulncheck.com/advisories/u-boot-rc3-buffer-overflow-in-nfs-readlink-reply-via-nfs-readlink
Exploit
https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/
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