CVE-2026-31535

In the Linux kernel, the following vulnerability has been resolved: smb: client: make use of 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.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/9911b1ed187a770a43950bf51f340ad4b7beecba	Patch
https://git.kernel.org/stable/c/be8845ad5d6558703d20567d8702155598325db8	Patch
https://git.kernel.org/stable/c/f664e6e8a81103cb45c8802a9bc7499e0902c458	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-04-24 15:16

Updated : 2026-06-17 10:33

NVD link : CVE-2026-31535

Mitre link : CVE-2026-31535

CVE.ORG link : CVE-2026-31535

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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