CVEvulnerability
CVE-2026-68288
- Status
- Received
- Published
- 2026-08-10
- Last modified
- 2026-10-03
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
net: drop_monitor: fix info leak in NET_DM_ATTR_PAYLOAD
net_dm_packet_report_fill() and net_dm_hw_packet_report_fill() open code
the NET_DM_ATTR_PAYLOAD attribute to avoid zeroing the packet payload
before overwriting it with skb_copy_bits().
skb_put() reserves nla_total_size(payload_len), i.e. the header plus the
NLA_ALIGN() padding, but only payload_len bytes are copied in. When
payload_len is not a multiple of 4 the 1-3 padding bytes are never
initialized and are leaked to user space inside the netlink message.
KMSAN confirms the leak for the software path when the packet payload
length is not 4-byte aligned:
BUG: KMSAN: kernel-infoleak in _copy_to_iter
_copy_to_iter
__skb_datagram_iter
skb_copy_datagram_iter
netlink_recvmsg
sock_recvmsg
__sys_recvfrom
Uninit was created at:
kmem_cache_alloc_node_noprof
__alloc_skb
net_dm_packet_work
Bytes 173-175 of 176 are uninitialized
Use __nla_reserve(), which sets up the attribute header and zeroes the
padding, instead of open coding the attribute construction.
References
- https://git.kernel.org/stable/c/05173de42a9923a3eaadebcb0dd5bc83ffba174c git.kernel.org
- https://git.kernel.org/stable/c/3c0bc7dcc5f9257d25c59eeb7ccb4df33dcfc446 git.kernel.org
- https://git.kernel.org/stable/c/5e9c8baee0329fbefe7c67aea945e2a07f15e98b git.kernel.org
- https://git.kernel.org/stable/c/89178ffe5bddc99c057ba2768db1f8d9c5e1408c git.kernel.org
- https://git.kernel.org/stable/c/8fd6975d2aecc36b25ee82b6aef88e62a3527ccb git.kernel.org
- https://git.kernel.org/stable/c/d427b152b663cb2b19fcd449d792e17edbe4a938 git.kernel.org