SB20260610130 - Red Hat Enterprise Linux 8 update for kernel-rt



SB20260610130 - Red Hat Enterprise Linux 8 update for kernel-rt

Published: June 10, 2026

Security Bulletin ID SB20260610130
CSH Severity
High
Patch available
YES
Number of vulnerabilities 13
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 8% Medium 23% Low 69%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 13 vulnerabilities.


1) Use-after-free (CVE-ID: CVE-2025-21858)

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 geneve_destroy_tunnels() function in drivers/net/geneve.c. A local user can escalate privileges on the system.


2) Use-after-free (CVE-ID: CVE-2023-53781)

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 __smc_create() function in net/smc/af_smc.c. A local user can escalate privileges on the system.


3) Use-after-free (CVE-ID: CVE-2025-68366)

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 nbd_genl_connect() function in drivers/block/nbd.c. A local user can escalate privileges on the system.


4) Out-of-bounds read (CVE-ID: CVE-2026-22984)

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 process_auth_done() function in net/ceph/messenger_v2.c. A local user can perform a denial of service (DoS) attack.


5) Input validation error (CVE-ID: CVE-2026-22990)

CWE-ID: CWE-20 - Improper input validation

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 improper input validation within the osdmap_apply_incremental() function in net/ceph/osdmap.c. A local user can perform a denial of service (DoS) attack.


6) Use After Free (CVE-ID: CVE-2026-23392)

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 execute arbitrary code or escalate privileges.

The vulnerability exists due to a use-after-free in the netfilter nf_tables component when handling flowtable hooks during error conditions. A local user can trigger a use-after-free condition by exploiting the improper release of a flowtable after an RCU grace period, leading to arbitrary code execution or privilege escalation.

Exploitation requires the ability to interact with the nfnetlink subsystem, typically available to local users with access to netfilter configuration interfaces.


7) Use-after-free (CVE-ID: CVE-2026-31581)

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 usb6fire_chip_abort() in the ALSA 6fire USB driver when handling device disconnect. A local user can trigger a device disconnect to cause a denial of service.

The issue occurs because the card private data may be freed synchronously when no file handles are open, after which the code accesses the freed chip structure.


8) Out-of-bounds read (CVE-ID: CVE-2026-31613)

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

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


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to out-of-bounds read in the SMB client symlink response parser when parsing a crafted symlink error response from an untrusted server. A remote attacker can send a specially crafted SMB response to disclose sensitive information.

The exposed heap bytes are UTF-16-decoded into the symlink target and returned to userspace via readlink(2).


9) Stack-based buffer overflow (CVE-ID: CVE-2026-43037)

CWE-ID: CWE-121 - Stack-based buffer overflow

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


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to a stack-based buffer overflow in ip4ip6_err() and __ip_options_echo() when processing a crafted packet that triggers ICMP error handling on a cloned skb. A remote attacker can send a specially crafted packet to execute arbitrary code.

The issue is caused by reusing skb cb[] data written by the IPv6 receive path as IPv4 metadata, allowing attacker-controlled packet data to influence the copied option length.


10) Out-of-bounds read (CVE-ID: CVE-2026-43038)

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

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 an out-of-bounds read in ip6_err_gen_icmpv6_unreach() when processing a forged ICMPv4 error containing a CIPSO IP option and an attacker-controlled inner IPv6 packet. A remote attacker can send a specially crafted ICMP error packet to cause a denial of service.

The issue arises because IPv4 control buffer data is reused as IPv6 control buffer data in a cloned skb, which can lead to a forged home address option offset being used during IPv6 TLV parsing.


11) Out-of-bounds write (CVE-ID: CVE-2026-43125)

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

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 an out-of-bounds write in dlm_search_rsb_tree() when processing network messages with an excessive resource name length. A remote attacker can send a specially crafted network message to cause a denial of service.

The length value originates from the len parameter in dlm_dump_rsb_name().


12) Double free (CVE-ID: CVE-2026-45852)

CWE-ID: CWE-415 - Double 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 double free in rxe_srq_from_init in the RDMA rxe subsystem when handling a failed copy_to_user operation during SRQ creation. A local user can trigger an error path to cause a denial of service.


13) Race condition (CVE-ID: CVE-2026-46181)

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

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 race condition in mlx4_srq_event() when handling RDMA SRQ events. A local user can trigger an event for a partially initialized srq object to cause a denial of service.

The issue can occur if an event is delivered before the srq object has finished initializing.


Remediation

Install update from vendor's website.