CVE-2026-74694

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net/ncsi: fix heap OOB read in NCSI_CMD_SEND_CMD payload length<br /> <br /> ncsi_send_cmd_nl() takes the number of bytes to copy from the<br /> attacker-controlled ncsi_pkt_hdr.length field of the in-band packet<br /> header, while the source buffer is the NCSI_ATTR_DATA netlink<br /> attribute whose readable size is nla_len() - sizeof(ncsi_pkt_hdr).<br /> The two length sources are never cross-checked: only<br /> nla_len() &gt;= sizeof(struct ncsi_pkt_hdr) is enforced.<br /> <br /> With hdr-&gt;length set larger than the attribute payload (up to 65535<br /> against at most 2032 readable bytes), ncsi_cmd_handler_oem() copies<br /> past the end of the netlink attribute buffer with unsafe_memcpy(),<br /> leaking up to ~64KB of kernel heap memory into the transmitted NCSI<br /> command packet. The destination skb is sized by the declared payload,<br /> so the write side does not overflow - this is a pure OOB read /<br /> information leak, reachable with CAP_NET_ADMIN on systems with a<br /> registered NCSI device (e.g. OpenBMC on Aspeed BMC SoCs, where<br /> NET_NCSI=y is standard).<br /> <br /> Reject commands whose declared payload extends past the end of the<br /> data attribute.<br /> <br /> The issue was found by the autokbug dynamic kernel fuzzer at Tencent<br /> Yunding Lab.