7.8
HIGH CVSS 3.1
CVE-2026-23066
rxrpc: Fix recvmsg() unconditional requeue
Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix recvmsg() unconditional requeue If rxrpc_recvmsg() fails because MSG_DONTWAIT was specified but the call at the front of the recvmsg queue already has its mutex locked, it requeues the call - whether or not the call is already queued. The call may be on the queue because MSG_PEEK was also passed and so the call was not dequeued or because the I/O thread requeued it. The unconditional requeue may then corrupt the recvmsg queue, leading to things like UAFs or refcount underruns. Fix this by only requeuing the call if it isn't already on the queue - and moving it to the front if it is already queued. If we don't queue it, we have to put the ref we obtained by dequeuing it. Also, MSG_PEEK doesn't dequeue the call so shouldn't call rxrpc_notify_socket() for the call if we didn't use up all the data on the queue, so fix that also.

INFO

Published Date :

Feb. 4, 2026, 5:16 p.m.

Last Modified :

April 3, 2026, 2:16 p.m.

Remotely Exploit :

No

Source :

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

The following products are affected by CVE-2026-23066 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.

ID Vendor Product Action
1 Linux linux_kernel
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Update Linux kernel to resolve recvmsg() queue corruption and potential UAFs or refcount issues.
  • Update the Linux kernel to the latest stable version.
  • Apply the specific patch for the rxrpc: Fix recvmsg() unconditional requeue.
  • Verify the integrity of the recvmsg queue after applying the fix.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-23066 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-2026-23066 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-2026-23066 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-23066 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.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Apr. 03, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Mar. 25, 2026

    Action Type Old Value New Value
    Added Reference https://git.kernel.org/stable/c/0464bf75590da75b8413c3e758c04647b4cdb3c6
    Added Reference https://git.kernel.org/stable/c/cf969bddd6e69c5777fa89dc88402204e72f312a
  • Initial Analysis by [email protected]

    Mar. 13, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-674
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.11 up to (excluding) 6.18.8
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/2c28769a51deb6022d7fbd499987e237a01dd63a Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/930114425065f7ace6e0c0630fab4af75e059ea8 Types: Patch
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Feb. 04, 2026

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix recvmsg() unconditional requeue If rxrpc_recvmsg() fails because MSG_DONTWAIT was specified but the call at the front of the recvmsg queue already has its mutex locked, it requeues the call - whether or not the call is already queued. The call may be on the queue because MSG_PEEK was also passed and so the call was not dequeued or because the I/O thread requeued it. The unconditional requeue may then corrupt the recvmsg queue, leading to things like UAFs or refcount underruns. Fix this by only requeuing the call if it isn't already on the queue - and moving it to the front if it is already queued. If we don't queue it, we have to put the ref we obtained by dequeuing it. Also, MSG_PEEK doesn't dequeue the call so shouldn't call rxrpc_notify_socket() for the call if we didn't use up all the data on the queue, so fix that also.
    Added Reference https://git.kernel.org/stable/c/2c28769a51deb6022d7fbd499987e237a01dd63a
    Added Reference https://git.kernel.org/stable/c/930114425065f7ace6e0c0630fab4af75e059ea8
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.