CVE-2026-29008 — U-Boot through 2026.04-rc3 contains an integer underflow...
CVE-2026-29008 漏洞深度分析
漏洞概述
CVE 编号： CVE-2026-29008
CVSS 评分： 8.7（HIGH）
CVSS 向量： CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE 分类： CWE-191
漏洞状态： Undergoing Analysis
发布时间： 2026-07-08T17:17:21.047
最后更新： 2026-07-14T19:16:55.150
漏洞描述
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.
影响分析
此漏洞的具体影响取决于实际利用场景。"
修复建议
- 及时关注厂商发布的安全更新和补丁
- 升级受影响组件到最新版本
- 如无法立即升级，参考厂商提供的临时缓解措施
- 加强网络访问控制和监控