SB2023101061 - Red Hat Enterprise Linux 8.6 Extended Update Support update for kernel
Published: October 10, 2023 Updated: January 4, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 12 secuirty vulnerabilities.
1) NULL pointer dereference (CVE-ID: CVE-2020-36558)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in the Linux kernel before 5.5.7 involving a VT_RESIZEX. A local user can perform a denial of service (DoS) attack.
2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2022-2503)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to the way dm-verity is used to restrict module/firmware loads to trusted root filesystem in LoadPin builds. Device-mapper table reloads currently allow users with root privileges to switch out the target with an equivalent dm-linear target and bypass verification till reboot. This allows root to bypass LoadPin and can be used to load untrusted and unverified kernel modules and firmware, which implies arbitrary kernel execution and persistence for peripherals that do not verify firmware updates.
3) Out-of-bounds read (CVE-ID: CVE-2022-2873)
The vulnerability allows a local user to crash the kernel.
The vulnerability exists due to a boundary condition within the Intel iSMT SMBus host controller driver. A local user can send specially crafted data to the I2C_SMBUS IOCTL, trigger an out-of-bounds read error and crash the system.
4) Resource management error (CVE-ID: CVE-2022-36879)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper management of internal resources within the xfrm_expand_policies() function in net/xfrm/xfrm_policy.c. A local user can cause the refcount to be dropped twice and perform a denial of service (DoS) attack.
5) Use-after-free (CVE-ID: CVE-2023-0590)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a use-after-free error within the qdisc_graft() function in net/sched/sch_api.c. A local user can trigger a use-after-free error and crash the kernel.
6) NULL pointer dereference (CVE-ID: CVE-2023-1095)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in the nf_tables_updtable() function within the netfilter subsystem. A local user can perform a denial of service (DoS) attack.
7) Resource exhaustion (CVE-ID: CVE-2023-1206)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a hash collision flaw in the IPv6 connection lookup table in the Linux kernel’s IPv6 functionality when an attacker makes a new kind of SYN flood attack. A remote attacker can increase the CPU usage of the server that accepts IPV6 connections up to 95%.
8) Use-after-free (CVE-ID: CVE-2023-2235)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in the Linux Kernel Performance Events system. A local user can trigger a use-after-free error and execute arbitrary code with elevated privileges.
9) Out-of-bounds write (CVE-ID: CVE-2023-3090)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error within the ipvlan network driver in Linux kernel. A local user can trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
10) Out-of-bounds write (CVE-ID: CVE-2023-35001)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error within the nft_byteorder() function. A local user can trigger an out-of-bounds write and execute arbitrary code on the target system.
11) Use-after-free (CVE-ID: CVE-2023-4004)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in the way a user triggers the nft_pipapo_remove function with the element, without a NFT_SET_EXT_KEY_END. A local user can execute arbitrary code with elevated privileges.
12) Use-after-free (CVE-ID: CVE-2023-4128)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error within net/sched/cls_fw.c in classifiers (cls_fw, cls_u32, and cls_route) in the Linux Kernel. A local user can trigger a use-after-free error and execute arbitrary code with elevated privileges.
Remediation
Install update from vendor's website.