Medium severity · published Jul 8, 2026
CVE-2026-29007
U-Boot 2026.04-rc3 Out-of-Bounds Read in tcp_rx_state_machine via tcp.c
5.3
CVSS
0.7%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UB
u-boot · u-boot
through 2026.04-rc3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-29007
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-29007
Mailing List
https://lists.denx.de/pipermail/u-boot/2026-May/617853.html
Product
https://u-boot.org/
Third Party Advisory
https://www.vulncheck.com/advisories/u-boot-rc3-out-of-bounds-read-in-tcp-rx-state-machine-via-tcp-c
Third Party Advisory
https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/
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