CVE detail
CVE-2026-29008
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.
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 16.1 · diversity 13.0 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 4
- within the 30d window
- Peak daily
- 4
- highest bucket
Evidence
Source links by recency
4 source links · newest first
- https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/y637f9qq2x.com
No excerpt available.
referencey637f9qq2x.comJul 8, 2026, 5:17 PM - https://www.vulncheck.com/advisories/u-boot-rc3-integer-underflow-dos-via-tcp-rx-state-machinewww.vulncheck.com
No excerpt available.
Exploitwww.vulncheck.comJul 8, 2026, 5:17 PM - https://u-boot.org/u-boot.org
No excerpt available.
referenceu-boot.orgJul 8, 2026, 5:17 PM No excerpt available.
referencelists.denx.deJul 8, 2026, 5:17 PM
Exploit code
Public exploit repository references
Public PoC repositories are third-party, potentially unsafe artifacts. Treat their code as untrusted and use it only on authorized systems in an isolated, least-privilege environment. cvebuzz does not execute the code or verify that an exploit works.
0 repository references · best confidence N/A · max 0 stars
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