ESB-2026.3977
PUBLISHED
CVSS 7.400000095367432 HIGH
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AUSCERT External Security Bulletin Redistribution
ESB-2026.3977
kernel security update
21 April 2026
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AUSCERT Security Bulletin Summary
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Product: kernel
Publisher: Red Hat
Operating System: Red Hat
Resolution: Patch/Upgrade
CVE Names: CVE-2026-23111 CVE-2026-23171 CVE-2026-23066
CVE-2026-23144 CVE-2026-23193 CVE-2026-23204
Original Bulletin:
https://access.redhat.com/errata/RHSA-2026:9112
Comment: CVSS (Max): 7.4 CVE-2026-23066 (CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)
CVSS Source: Red Hat
Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (Max): 0.0% (8th) CVE-2026-23193 2026-04-20
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RHSA-2026:9112 - Security Advisory
Issued: 2026-04-20
Updated: 2026-04-20
Synopsis
Kernel security update
Type/Severity
Security Advisory: Moderate
Topic
An update for kernel is now available for Red Hat Enterprise Linux 9.6 Extended
Update Support.
Red Hat Product Security has rated this update as having a security impact of
Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives
a detailed severity rating, is available for each vulnerability from the CVE
link(s) in the References section.
Description
The kernel packages contain the Linux kernel, the core of any Linux operating
system.
Security Fix(es):
o kernel: Linux kernel: Denial of Service via unsafe requeue in rxrpc_recvmsg
(CVE-2026-23066)
o kernel: Kernel: Privilege escalation or denial of service in nf_tables via
inverted element activity check (CVE-2026-23111)
o kernel: Linux kernel: Local denial of service and memory leak in DAMON
sysfs via setup failure (CVE-2026-23144)
o kernel: Linux kernel: Use-after-free in bonding module can cause system
crash or arbitrary code execution (CVE-2026-23171)
o kernel: scsi: target: iscsi: Fix use-after-free in
iscsit_dec_session_usage_count() (CVE-2026-23193)
o kernel: net/sched: cls_u32: use skb_header_pointer_careful()
(CVE-2026-23204)
For more details about the security issue(s), including the impact, a CVSS
score, acknowledgments, and other related information, refer to the CVE page(s)
listed in the References section.
Solution
For details on how to apply this update, which includes the changes described
in this advisory, refer to:
https://access.redhat.com/articles/11258
The system must be rebooted for this update to take effect.
Affected Products
o Red Hat Enterprise Linux for x86_64 - Extended Update Support 9.6 x86_64
o Red Hat Enterprise Linux Server - AUS 9.6 x86_64
o Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 9.6
s390x
o Red Hat Enterprise Linux for Power, little endian - Extended Update Support
9.6 ppc64le
o Red Hat Enterprise Linux for ARM 64 - Extended Update Support 9.6 aarch64
o Red Hat Enterprise Linux Server for Power LE - Update Services for SAP
Solutions 9.6 ppc64le
o Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.6
x86_64
o Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 9.6
x86_64
o Red Hat CodeReady Linux Builder for Power, little endian - Extended Update
Support 9.6 ppc64le
o Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support
9.6 s390x
o Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 9.6
aarch64
o Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.6 aarch64
o Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.6 s390x
o Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.6 x86_64
o Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.6 aarch64
o Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.6
ppc64le
o Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.6 s390x
Fixes
o BZ - 2436805 - CVE-2026-23066 kernel: Linux kernel: Denial of Service via
unsafe requeue in rxrpc_recvmsg
o BZ - 2439687 - CVE-2026-23111 kernel: Kernel: Privilege escalation or
denial of service in nf_tables via inverted element activity check
o BZ - 2439872 - CVE-2026-23144 kernel: Linux kernel: Local denial of service
and memory leak in DAMON sysfs via setup failure
o BZ - 2439886 - CVE-2026-23171 kernel: Linux kernel: Use-after-free in
bonding module can cause system crash or arbitrary code execution
o BZ - 2439887 - CVE-2026-23193 kernel: scsi: target: iscsi: Fix
use-after-free in iscsit_dec_session_usage_count()
o BZ - 2439931 - CVE-2026-23204 kernel: net/sched: cls_u32: use
skb_header_pointer_careful()
CVEs
o CVE-2026-23066
o CVE-2026-23111
o CVE-2026-23144
o CVE-2026-23171
o CVE-2026-23193
o CVE-2026-23204
References
o https://access.redhat.com/security/updates/classification/#moderate
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