CVE-2026-29008: U-Boot 2026.04-rc3 Integer Underflow DoS via tcp_rx_state_machine()
Affected: u-boot · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 53% of scored CVEs
DescriptionCVE.org
U-Boot through 2026.04-rc3 contains an integer underflow vulnerability in the tcp_rx_state_machine() function (net/tcp.c) that allows a network-adjacent attacker to crash the bootloader by sending a malformed TCP SYN+ACK packet with a manipulated data offset field causing payload_len to become negative. When the TCP_SYN_SENT handler calls tcp_rx_user_data() without invoking tcp_seg_in_wnd() validation, the negative payload_len is implicitly converted to a large unsigned integer (e.g., 0xFFFFFFD8) and passed to memcpy() in store_block(), causing an immediate crash that prevents device boot and may enable memory corruption when CONFIG_LMB is disabled.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- u-boot · u-bootup to and including 2026.04-rc3
On the Atlas
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CoverageNo articles yet
No CyberSIXT article names CVE-2026-29008 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.