CVE-2026-31539: Linux Kernel

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: smb: smbdirect: introduce smbdirect_socket.recv_io.credits.available The logic off managing recv credits by counting posted recv_io and granted credits is racy. That's because the peer might already consumed a credit, but between receiving the incoming recv at the hardware and processing the completion in the 'recv_done' functions we likely have a window where we grant credits, which don't really exist. So we better have a decicated counter for the available credits, which will be incremented when we posted new recv buffers and drained when we grant the credits to the peer.

Affected products

• Linux Linux Kernel: from 6.18, before 6.18.11 (fixed in 6.18.11); from 6.19, before 6.19.1 (fixed in 6.19.1)

Published 2026-04-24. Last modified 2026-06-17.