0.0
NA
CVE-2026-31539
smb: smbdirect: introduce smbdirect_socket.recv_io.credits.available
Description

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.

INFO

Published Date :

April 24, 2026, 3:16 p.m.

Last Modified :

April 24, 2026, 3:16 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-31539 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Fix a race condition in SMB3 Direct credit management logic.
  • Update the Linux kernel to the latest stable version.
  • Apply the relevant patch for smbdirect_socket.recv_io.credits.available.
  • Ensure credit management logic handles posted and granted credits correctly.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-31539.

URL Resource
https://git.kernel.org/stable/c/6e3c5052f9686192e178806e017b7377155f4bab
https://git.kernel.org/stable/c/e811e60e1cc79923c4388146eb1fa26a7482731e
https://git.kernel.org/stable/c/f99996870222b598914a1f49d7375dc23752c237
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-31539 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-31539 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-31539 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-31539 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Apr. 24, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added Reference https://git.kernel.org/stable/c/6e3c5052f9686192e178806e017b7377155f4bab
    Added Reference https://git.kernel.org/stable/c/e811e60e1cc79923c4388146eb1fa26a7482731e
    Added Reference https://git.kernel.org/stable/c/f99996870222b598914a1f49d7375dc23752c237
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.