SB2026090267 - Red Hat Enterprise Linux 10 update for kernel



SB2026090267 - Red Hat Enterprise Linux 10 update for kernel

Published: September 2, 2026

Security Bulletin ID SB2026090267
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 6
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 6 vulnerabilities.


1) Improper access control (CVE-ID: CVE-2026-46150)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to bypass permission checks.

The vulnerability exists due to improper access control in fsnotify_get_mark_safe() when processing fanotify permission events. A local user can trigger permission events in the presence of an unrelated detached mark to bypass permission checks.


2) Use-after-free (CVE-ID: CVE-2026-46120)

CWE-ID: CWE-416 - Use After 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 a use-after-free in ip6erspan_changelink() when changing link configuration after network namespace migration. A local user can trigger tunnel reinsertion into the wrong per-netns hash to cause a denial of service.

The issue is reachable from an unprivileged user namespace.


3) Race condition (CVE-ID: CVE-2026-53361)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/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 race condition in unix_gc() and unix_peek_fpl() in the af_unix garbage collection logic when processing MSG_PEEK operations during garbage collection scheduling. A local user can trigger concurrent garbage collection activity to cause a denial of service.

The issue occurs because gc_in_progress may be false while unix_gc() is running, which can confuse garbage collection by MSG_PEEK.


4) Use-after-free (CVE-ID: CVE-2026-64002)

CWE-ID: CWE-416 - Use After 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 a use-after-free in ipv4_sysctl_exit_net() when unregistering the IPv4 sysctl table while sysctl handlers may still access sysctl_local_reserved_ports. A local user can trigger access to the freed sysctl entry to cause a denial of service.

The issue affects access to /proc/sys/net/ipv4/ip_local_reserved_ports during network namespace sysctl teardown.


5) Use-after-free (CVE-ID: CVE-2026-74480)

CWE-ID: CWE-416 - Use After 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 a use-after-free in br_multicast_leave_group() in the bridge multicast handling code when processing fast-leave operations on port groups. A local user can trigger deletion of a matching port group to cause a denial of service.

The issue can occur when multicast-to-unicast had been enabled, allowing multiple port groups for the same port and group with different source MAC addresses, and is later disabled so entries are matched by port only.


6) Use-after-free (CVE-ID: CVE-2026-74581)

CWE-ID: CWE-416 - Use After 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 a use-after-free in fib6_rule_lookup() and fib6_rule_suppress() in the IPv6 routing rules handler when processing suppressed IPv6 route lookups. A local user can trigger route lookups involving a suppressing rule to cause a denial of service.

The issue occurs because a stale dst entry can be returned after the released route remains referenced in the lookup result.


Remediation

Install update from vendor's website.