SB2026072842 - Red Hat Enterprise Linux 10 update for kernel



SB2026072842 - Red Hat Enterprise Linux 10 update for kernel

Published: July 28, 2026

Security Bulletin ID SB2026072842
CSH Severity
High
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 20% Medium 20% Low 60%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 vulnerabilities.


1) NULL pointer dereference (CVE-ID: CVE-2026-46086)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.8 [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]


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

The vulnerability exists due to a null pointer dereference in br_fdb_fillbuf() when reading bridge forwarding database entries through the brforward_read() sysfs path during a concurrent local FDB update. A local user can trigger concurrent access to cause a denial of service.

The issue arises because RCU readers can observe inconsistent values of f->dst across a check and a later dereference.


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

CWE-ID: CWE-416 - Use After Free

CVSSv4: 8.7 [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]


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.


3) Double free (CVE-ID: CVE-2026-52993)

CWE-ID: CWE-415 - Double Free

CVSSv4: 6.8 [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]


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

The vulnerability exists due to double free in tipc_buf_append() when validating a reassembled skb after tipc_msg_validate() reallocates it. A local user can trigger the error-handling path with a crafted TIPC message to cause a denial of service.


4) Use-after-free (CVE-ID: CVE-2026-53281)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service or execute arbitrary code.

The vulnerability exists due to a NULL pointer dereference and use-after-free in the Intel VT-d IOMMU PASID teardown logic when detaching a domain that was not attached to the IOMMU or when a PASID entry is not found. A local user can trigger teardown operations on an invalid or missing PASID association to cause a denial of service or execute arbitrary code.

The issue can also corrupt reference counts, which may prematurely drop a shared domain reference to zero for remaining active devices.


5) Resource management error (CVE-ID: CVE-2026-43500) Exploited

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: 9.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H]


The vulnerability allows a local user to escalate privileges on the system.

The RxRPC Page-Cache Write vulnerability exists due to improper management of internal resources. A local user can execute arbitrary code with root privileges.

Note, this vulnerability is one of two issues described as Dirty Frag.


Remediation

Install update from vendor's website.