CVE-2026-29008

Katalog CVE

CVSS 7.5 · High EPSS 0,71%

Kerentanan Integer Underflow (Wrap or Wraparound) pada denx u-boot. Skor CVSS 3.1 7.5 (High) menurut vulncheck.com.

Deskripsi (NVD)

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.

Rincian

Terbit di NVD

8 Juli 2026

Terakhir diubah

22 Juli 2026

Status NVD

Analyzed

CVSS 3.1

7.5 (High), sumber vulncheck.com
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-191: Integer Underflow (Wrap or Wraparound)

EPSS (30 hari)

0,71% peluang dieksploitasi; lebih tinggi dari 52,1% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://lists.denx.de/pipermail/u-boot/2026-May/617853.html mailing list · advisory pihak ketiga
• https://www.vulncheck.com/advisories/u-boot-rc3-integer-underflow-dos-via-tcp-rx-state-machine advisory pihak ketiga · exploit
• https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/ advisory pihak ketiga · exploit
• https://u-boot.org/ product