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OpenAdvisories
Medium · 5.3 CVE-2026-29007 EUVD-2026-42328GHSA-572m-4pr8-48pj

U-Boot 2026.04-rc3 Out-of-Bounds Read in tcp_rx_state_machine via tcp.c

Published Jul 8, 2026 · Updated Jul 14, 2026 · Assigned by VulnCheck

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.

Affected products

VendorProductAffectedFixed
u-boot u-boot ≤ 2026.04-rc3 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 u-boot No fix yet —
Debian 13 u-boot No fix yet —
Debian 12 u-boot No fix yet —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 u-boot No fix yet —
Ubuntu 26.04 LTS u-boot No fix yet —
Ubuntu 25.10 u-boot No fix yet —
Ubuntu 24.04 LTS u-boot +1 No fix yet —
Ubuntu 22.04 LTS u-boot +1 No fix yet —
Show 3 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu Pro 20.04 LTS u-boot No fix yet —
Ubuntu Pro 18.04 LTS u-boot No fix yet —
Ubuntu Pro 16.04 LTS u-boot No fix yet —

Advisories 1

References