Vulnerabilities
- CVSS
- 5.5 Medium
- Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H- EPSS
- 0.18%
- Risk score
- 4.0
- Published
- 2026-08-22
- Status
- Published
In the Linux kernel, the following vulnerability has been resolved:
net/ncsi: fix heap OOB read in NCSI_CMD_SEND_CMD payload length
ncsi_send_cmd_nl() takes the number of bytes to copy from the
attacker-controlled ncsi_pkt_hdr.length field of the in-band packet
header, while the source buffer is the NCSI_ATTR_DATA netlink
attribute whose readable size is nla_len() - sizeof(ncsi_pkt_hdr).
The two length sources are never cross-checked: only
nla_len() >= sizeof(struct ncsi_pkt_hdr) is enforced.
With hdr->length set larger than the attribute payload (up to 65535
against at most 2032 readable bytes), ncsi_cmd_handler_oem() copies
past the end of the netlink attribute buffer with unsafe_memcpy(),
leaking up to ~64KB of kernel heap memory into the transmitted NCSI
command packet. The destination skb is sized by the declared payload,
so the write side does not overflow - this is a pure OOB read /
information leak, reachable with CAP_NET_ADMIN on systems with a
registered NCSI device (e.g. OpenBMC on Aspeed BMC SoCs, where
NET_NCSI=y is standard).
Reject commands whose declared payload extends past the end of the
data attribute.
The issue was found by the autokbug dynamic kernel fuzzer at Tencent
Yunding Lab.
A flaw was found in the Linux kernel's NCSI (Network Controller Sideband Interface) component. A local attacker with CAP_NET_ADMIN capabilities could exploit a heap out-of-bounds (OOB) read vulnerability. By crafting a malicious NCSI command with an oversized payload length, the attacker could cause the kernel to read past the intended buffer. This could lead to the disclosure of up to 64KB of sensitive kernel heap memory.
Coverage 1
threat-intel
Multiple vulnerabilities have been discovered in the Linux kernel of Debian. These vulnerabilities allow for privilege escalation, data compromise, and denial of service. The affected Debian versions are prior to 6.12.10…
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