SB20260420135 - Red Hat Enterprise Linux 9 update for kernel

Description

This security bulletin contains information about 6 vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2026-23066)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to a use-after-free error within the rxrpc_recvmsg() function in net/rxrpc/recvmsg.c. A local user can escalate privileges on the system.

2) Use-after-free (CVE-ID: CVE-2026-23111)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to a use-after-free error within the nft_map_catchall_activate() function in net/netfilter/nf_tables_api.c. A local user can escalate privileges on the system.

3) Memory leak (CVE-ID: CVE-2026-23144)

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

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 memory leak within the damon_sysfs_context_add_dirs() function in mm/damon/sysfs.c. A local user can perform a denial of service (DoS) attack.

4) Use-after-free (CVE-ID: CVE-2026-23171)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to a use-after-free error within the bond_enslave() function in drivers/net/bonding/bond_main.c. A local user can escalate privileges on the system.

5) Use-after-free (CVE-ID: CVE-2026-23193)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to a use-after-free error within the iscsit_dec_session_usage_count() function in drivers/target/iscsi/iscsi_target_util.c. A local user can escalate privileges on the system.

6) Out-of-bounds read (CVE-ID: CVE-2026-23204)

CWE-ID: CWE-125 - Out-of-bounds read

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 an out-of-bounds read error within the u32_classify() function in net/sched/cls_u32.c. A local user can perform a denial of service (DoS) attack.

Remediation

Install update from vendor's website.

References

• https://access.redhat.com/errata/RHSA-2026:9112