CVE-2026-23066 | rxrpc: Fix recvmsg() unconditional requeue

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.

Published: 2026-02-04 Last update: 2026-06-01 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-23066 is rated Low Risk (32.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-23066

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-05 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-23066

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 416baaa9-dc9f-4396-8d5f-8c081fb06d67
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2026-23066

GitHub Security Advisory for CVE-2026-23066

GHSA-rx25-rppp-x99w · Severity: medium — In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix recvmsg()...

OS Trackers for CVE-2026-23066

vendor priority summary link
debian not yet assigned CVE-2026-23066 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2026-23066
redhat medium — https://access.redhat.com/security/cve/CVE-2026-23066
suse high CVE-2026-23066 severity important: SUSE including 134 source package names (2.2.1-5.81:libblkid1-2.40.4-slfo.1.1_4.1, 2.2.1-5.81:libfdisk1-2.40.4-slfo.1.1_4.1, …), 389 product×package rows across 40 product lines (Container suse/sl-micro/6.1/baremetal-os-container, Container suse/sl-micro/6.1/base-os-container, … (40 product lines)): Fixed 227, Known Not Affected 137, First Fixed 25. https://www.suse.com/security/cve/CVE-2026-23066/
ubuntu medium CVE-2026-23066 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1256 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): DNE 871, ignored 170, needed 124, released 83, not-affected 8. https://ubuntu.com/security/CVE-2026-23066

Affected software / configurations for CVE-2026-23066

Vendor Product Version Raw CPE
linux linux_kernel >= 4.11, < 6.18.8 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 6.19 cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*
linux linux_kernel 6.19 cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*
linux linux_kernel 6.19 cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*
linux linux_kernel 6.19 cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*
linux linux_kernel 6.19 cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*
linux linux_kernel 6.19 cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*

References for CVE-2026-23066

cvelogic Threat Intelligence