SB2026061712 - Red Hat Enterprise Linux 9 update for kernel

Description

This security bulletin contains information about 20 vulnerabilities.

1) Input validation error (CVE-ID: CVE-2025-40170)

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 sk_clone_lock(), sk_dst_gso_max_size() and sk_setup_caps() functions in net/core/sock.c. A local user can perform a denial of service (DoS) attack.

2) Use-after-free (CVE-ID: CVE-2025-40135)

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 ip6_autoflowlabel() and ip6_xmit() functions in net/ipv6/ip6_output.c. A local user can escalate privileges on the system.

3) Use-after-free (CVE-ID: CVE-2025-40158)

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 ip6_finish_output2() and ip6_finish_output() functions in net/ipv6/ip6_output.c. A local user can escalate privileges on the system.

4) 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.

5) Integer overflow (CVE-ID: CVE-2025-68724)

CWE-ID: CWE-190 - Integer overflow

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.

The vulnerability exists due to integer overflow within the asymmetric_key_generate_id() function in crypto/asymmetric_keys/asymmetric_type.c. A local user can execute arbitrary code.

6) Double free (CVE-ID: CVE-2025-71089)

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 perform a denial of service (DoS) attack.

The vulnerability exists due to a double free error within the iommu_sva_bind_device() function in drivers/iommu/iommu-sva.c. A local user can perform a denial of service (DoS) attack.

7) Out-of-bounds read (CVE-ID: CVE-2025-71116)

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

8) 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.

9) 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.

10) Use-after-free (CVE-ID: CVE-2026-23216)

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_conn_usage_count() function in drivers/target/iscsi/iscsi_target_util.c. A local user can escalate privileges on the system.

11) 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.

12) Out-of-bounds read (CVE-ID: CVE-2026-23455)

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 an out-of-bounds read in DecodeQ931() in the nf_conntrack_h323 netfilter component when parsing a crafted Q.931 packet with a zero UserUserIE length field. A remote attacker can send a specially crafted packet to disclose sensitive information.

The issue occurs because a 16-bit length value is decremented by 1 to skip the protocol discriminator byte, and an encoded length of 0 wraps to -1 and is then passed to DecodeH323_UserInformation() as a large value.

13) Improper input validation (CVE-ID: CVE-2026-31685)

CWE-ID: CWE-20 - Improper input validation

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 improper input validation in ip6t_eui64 when processing packets with an invalid MAC header. A remote attacker can send a specially crafted packet to cause a denial of service.

14) Use-after-free (CVE-ID: CVE-2026-43116)

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 netfilter ctnetlink expectation handling when processing expectation add, delete, get, or event operations. A local user can trigger access to an invalid master conntrack object to cause a denial of service.

15) Out-of-bounds read (CVE-ID: CVE-2026-43190)

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

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

The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to an out-of-bounds read in the xt_tcpmss TCP option parser when parsing a TCP option field whose last byte is not EOL or NOP. A local user can supply a specially crafted packet to disclose sensitive information.

16) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-43158)

CWE-ID: CWE-664 - Improper control of a resource through its 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 cause a denial of service.

The vulnerability exists due to improper state management in the xfs extended attribute leaf block freemap adjustment code when adding extended attributes to leaf blocks. A local user can set a crafted extended attribute to cause a denial of service.

The issue can corrupt free space accounting so that the name area overlaps the end of the entries array, triggering an assertion and shutting down the filesystem.

17) Use-after-free (CVE-ID: CVE-2026-43303)

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 use-after-free in the swap subsystem when handling stale page->private values on reallocated and split pages. A local user can trigger swapoff operations after causing affected page state reuse to cause a denial of service.

The issue occurs because tail pages can retain stale page->private values after split_page(), leading swap_count_continued() to follow an invalid continuation list and access poisoned list entries.

18) Improper input validation (CVE-ID: CVE-2026-46243)

CWE-ID: CWE-20 - Improper input validation

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 disclose sensitive information, modify data, or cause a denial of service.

The vulnerability exists due to improper input validation in the cifs.spnego key description handling in fs/smb/client/cifs_spnego.c when processing userspace-created cifs.spnego keys through request_key(2) or add_key(2). A local user can supply a crafted cifs.spnego description to disclose sensitive information, modify data, or cause a denial of service.

The issue arises because authority-bearing fields such as pid, uid, creduid, and upcall_target may be treated by cifs.upcall as kernel-originating inputs.

19) Use-after-free (CVE-ID: CVE-2026-46227)

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.

The vulnerability exists due to a use-after-free and type confusion in sctp_sendmsg() SCTP_SENDALL path when iterating associations after sctp_sendmsg_to_asoc() drops and reacquires the socket lock. A local user can trigger concurrent association migration or freeing to execute arbitrary code.

The issue is reachable with no effective capabilities, and the type-confusion path can lead to a controlled indirect call via the outqueue.sched->init_sid pointer.

20) Use-after-free (CVE-ID: CVE-2026-46125)

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 debugfs when handling failed connection preparation for mlo connections. A local user can trigger connection preparation failure and access the affected debugfs state to cause a denial of service.

The issue occurs when debugfs is enabled and an interface is reset from mld to non-mld, which recreates its debugfs entries.

Remediation

Install update from vendor's website.

References

• https://access.redhat.com/errata/RHSA-2026:26515