SB2026072449 - Red Hat Enterprise Linux 9 update for kernel



SB2026072449 - Red Hat Enterprise Linux 9 update for kernel

Published: July 24, 2026

Security Bulletin ID SB2026072449
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 20% Low 80%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 vulnerabilities.


1) Resource management error (CVE-ID: CVE-2025-40026)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to resource management error within the emulator_is_smm() and x86_emulate_instruction() functions in arch/x86/kvm/x86.c. A local user can perform a denial of service (DoS) attack.


2) Out-of-bounds write (CVE-ID: CVE-2026-53059)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to an out-of-bounds write in create_log_context() and dm-log bitset handling when processing a crafted device-mapper mirror target configuration with an oversized region count. A local user can create a crafted mirror target to cause a denial of service.

The issue is triggered when region_count overflows 32 bits, causing bitsets to be allocated smaller than required and later accessed with indices derived from the full region space.


3) Use-after-free (CVE-ID: CVE-2026-52976)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in xe_exec_queue_create_ioctl() when handling crafted ioctl requests that trigger error cleanup paths. A local user can trigger queue creation failures to cause a denial of service.

One affected path leaves a freed queue linked in the VM compute exec queue list in preempt fence mode, and another leaves a freed queue linked in the hardware engine group list.


4) Use-after-free (CVE-ID: CVE-2026-52950)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in the drm/xe dma-buf import handling in xe_gem_prime_import() when processing a dma-buf attachment with the retry loop. A local user can trigger an error path that frees the backing object and then causes it to be reused to cause a denial of service.


5) Use-after-free (CVE-ID: CVE-2026-53006)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a use-after-free in icmpv6_rcv() in the IPv6 ICMP handling code when processing ICMPv6 packets. A remote attacker can send a specially crafted ICMPv6 packet to cause a denial of service.


Remediation

Install update from vendor's website.