CVE-2026-29007

U-Boot through 2026.04-rc3 contains an out-of-bounds read vulnerability in tcp_rx_state_machine() (net/tcp.c) when CONFIG_PROT_TCP is enabled, allowing remote attackers to read beyond TCP segment boundaries by crafting a malicious packet with a mismatched IP total length and TCP data offset field. Attackers can send a packet with an IP total length of 40 bytes and a TCP data offset claiming 60 bytes of header to cause tcp_parse_options() to read 40 bytes past the end of the TCP segment, potentially corrupting connection state variables such as rmt_win_scale and rmt_timestamp to disrupt TCP window calculations.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
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-out-of-bounds-read-in-tcp-rx-state-machine-via-tcp-c	Third Party Advisory Exploit
https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/	Third Party Advisory Exploit

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 : 2026-07-22 18:31

NVD link : CVE-2026-29007

Mitre link : CVE-2026-29007

CVE.ORG link : CVE-2026-29007

JSON object : View

Products Affected

denx

u-boot

CWE

CWE-125

Out-of-bounds Read

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