SB20260921120 - Red Hat Enterprise Linux 10 update for kernel

Description

This security bulletin contains information about 25 vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2026-52924)

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 use-after-free in the SCTP outqueue and stream scheduler state handling when processing a stale COOKIE-ECHO condition. A remote attacker can send a stale cookie error during SCTP association handling to cause a denial of service.

The issue occurs when an association is rolled back from COOKIE_ECHOED to COOKIE_WAIT, leaving scheduler state referencing freed stream entries.

2) Heap-based buffer overflow (CVE-ID: CVE-2026-74556)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

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 heap-based buffer overflow in iscsi_tcp_hdr_dissect() in libiscsi_tcp when processing a crafted iSCSI SCSI Command Response pdu. A remote attacker can send a specially crafted response with an oversized data segment to cause a denial of service.

The issue occurs because sense or response data for ISCSI_OP_SCSI_CMD_RSP can exceed the fixed 8192-byte connection buffer while remaining within the negotiated maximum receive data segment length.

3) Use-after-free (CVE-ID: CVE-2026-68426)

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 validate_xmit_xfrm() in net/xfrm/xfrm_device.c when processing GSO segment lists with asynchronous crypto handling. A local user can trigger asynchronous processing that steals a segment and leaves a stale skb->prev pointer to cause a denial of service.

The issue occurs when a stolen segment remains referenced as the list tail and is later dereferenced by validate_xmit_skb_list().

4) Out-of-bounds write (CVE-ID: CVE-2026-68264)

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

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 an out-of-bounds write in xe_pt_update_ops_init() and the vm_bind path in the xe driver when retrying page table update preparation after lock contention or OOM eviction. A local user can trigger repeated retries to cause a denial of service.

The issue can corrupt SLUB-poisoned memory and lead to a subsequent use-after-free crash in xe_migrate_update_pgtables_cpu().

5) Improper locking (CVE-ID: CVE-2026-64111)

CWE-ID: CWE-667 - Improper Locking

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to bypass security restrictions.

The vulnerability exists due to improper locking in lsm_set_self_attr() when setting a process security attribute. A local user can invoke the syscall while the process is being ptraced to bypass security restrictions.

This affects SELinux and AppArmor checks related to ptrace during security context transitions.

6) Use-after-free (CVE-ID: CVE-2026-63917)

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 the vti6 tunnel handling code in net/ipv6/ip6_vti.c when changing the configuration of a vti6 device after moving it across network namespaces. A local user can move a vti6 device between namespaces and then change its link parameters to cause a denial of service.

The issue is reachable from an unprivileged user namespace and may have cross-tenant impact on container hosts.

7) Use-after-free (CVE-ID: CVE-2026-63919)

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 xfrm transport-mode deferred reinjection handling in net/xfrm/xfrm_input.c when processing deferred transport reinjection callbacks that use a stored network namespace pointer. A local user can trigger deferred transport reinjection with a dangling net namespace reference to cause a denial of service.

8) Improper access control (CVE-ID: CVE-2026-63921)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to redirect packets across network namespaces.

The vulnerability exists due to improper access control in vti6_siocdevprivate() in the IPv6 VTI tunnel handling code when processing SIOCCHGTUNNEL requests on a migrated tunnel. A local user can supply tunnel parameters that collide with a tunnel in the creation namespace to redirect packets across network namespaces.

Exploitation is reachable from an unprivileged user namespace and can have cross-tenant scope on container hosts.

9) Integer overflow (CVE-ID: CVE-2026-63889)

CWE-ID: CWE-190 - Integer overflow

CVSSv4: 7.1 [CVSS:4.0/AV:A/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 an infinite loop caused by an integer truncation error in the FPIN pname walker in scsi_transport_fc when processing a crafted FPIN ELS frame. A remote attacker can send a crafted Fibre Channel fabric frame to cause a denial of service.

Exploitation requires the ability to inject Fibre Channel fabric traffic to an lpfc or qla2xxx Linux initiator, such as from a compromised switch or fabric controller, or from a same-zone N_Port on a fabric that permits source spoofing.

10) 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.

11) Use-after-free (CVE-ID: CVE-2026-53239)

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 xfrm_policy_bysel_ctx() and inexact bin handling in the xfrm policy subsystem when processing concurrent policy deletion and hash rebuild operations. A local user can trigger a race condition to cause a denial of service.

The issue occurs because an inexact bin may be freed during a window after the policy lock is released and before pruning is performed.

12) Out-of-bounds read (CVE-ID: CVE-2026-53246)

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

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to disclose sensitive information or cause memory corruption.

The vulnerability exists due to an out-of-bounds read in sctp_unpack_cookie() and cached peer INIT chunk processing when processing a crafted COOKIE_ECHO chunk. A remote attacker can send a specially crafted COOKIE_ECHO chunk with an inflated cached INIT chunk length to disclose sensitive information or cause memory corruption.

The issue occurs in a listening SCTP server while walking parameters from the cached peer INIT chunk embedded after the cookie.

13) Improper input validation (CVE-ID: CVE-2026-53131)

CWE-ID: CWE-20 - Improper input validation

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 improper input validation in netfilter Ethernet header handling when processing packets that reach ip6t_eui64, xt_mac, ipset bitmap:ip,mac, hash:ip,mac, hash:mac, or nf_log_syslog code paths without a valid Ethernet MAC header. A remote attacker can send a specially crafted packet to cause a denial of service.

The issue occurs because these paths access eth_hdr(skb) after insufficient validation that the skb is associated with an Ethernet device and that a full MAC header is present.

14) Use-after-free (CVE-ID: CVE-2025-40149)

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 escalate privileges on the system.

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

15) Out-of-bounds read (CVE-ID: CVE-2026-46149)

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

CVSSv4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to an out-of-bounds read in tg_pt_gp_members_show() when formatting and copying LUN paths to a sysfs reader. A local user can read the affected sysfs entry with a long fabric WWN value to disclose sensitive information.

When CONFIG_FORTIFY_SOURCE is enabled, exploitation triggers fortify_panic() instead of leaking adjacent stack contents.

16) Use-after-free (CVE-ID: CVE-2026-43370)

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 race in VM acquire when parent and child processes sharing a drm_file both try to acquire the same VM after fork(). A local user can trigger concurrent VM acquisition to cause a denial of service.

The issue occurs in scenarios involving fork() with shared drm_file state between parent and child processes.

17) Integer overflow (CVE-ID: CVE-2026-43368)

CWE-ID: CWE-190 - Integer overflow

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 an integer overflow in the i915 GEM shmem scatterlist handling when populating a scatterlist table with folio-backed pages for a GEM shmem object of size 4 gb or more. A local user can trigger a page fault on a specially crafted large object to cause a denial of service.

The issue can occur if the total byte length recorded in a single scatterlist reaches or crosses the 4 gb limit, leading to an unexpected premature end of the object's backing pages.

18) Out-of-bounds write (CVE-ID: CVE-2026-43248)

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

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 an out-of-bounds write in vdpa_sim when assigning an ASID to a group. A local user can assign a valid ASID to a group equal to ngroups to cause a denial of service.

19) Race condition (CVE-ID: CVE-2026-31539)

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

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 race condition in smbdirect credit management when processing incoming SMB Direct receive operations. A remote attacker can send network traffic that triggers incorrect credit granting to cause a denial of service.

20) Use-after-free (CVE-ID: CVE-2026-31656)

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 use-after-free in intel_engine_park_heartbeat when racing the heartbeat worker and request retirement paths while releasing engine->heartbeat.systole. A local user can trigger concurrent request retirement and heartbeat handling to cause a denial of service.

The issue arises because the same systole request can be released twice after a stale non-NULL pointer is observed in a non-atomic read-and-clear sequence.

21) Use-after-free (CVE-ID: CVE-2026-31663)

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 xfrm_input_resume and transport_finish when processing packets after asynchronous crypto completion. A local user can trigger a race with device teardown to cause a denial of service.

22) Use-after-free (CVE-ID: CVE-2026-31566)

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 amdgpu_amdkfd_submit_ib() when waiting for GPU job completion after submitting a GPU job. A local user can trigger the vulnerable code path to cause a denial of service.

23) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-31479)

CWE-ID: CWE-664 - Improper control of a resource through its lifetime

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 improper state management in the xe virtual memory bind/unwind handling in drm/xe when processing crafted VM bind and rebind operations during 3D workloads. A local user can trigger bind operations that cause overlapping VMA re-insertion and leave the VM in a bad state to cause a denial of service.

The issue can be triggered on the unwind path, including with a vector of binds, when a rebind occurs in the middle of a VMA and compatible mapped ends are skipped.

24) Improper access control (CVE-ID: CVE-2026-23466)

CWE-ID: CWE-284 - Improper Access Control

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 improper access control in GGTT MMIO access protection when tearing down the xe driver after a failed driver load or asynchronous buffer object cleanup. A local user can trigger access to the GGTT MMIO region after teardown begins to cause a denial of service.

The issue occurs because existing protection based on drm_dev_enter is insufficient if driver load fails, and buffer objects with GGTT mappings may be freed asynchronously by worker threads.

25) Double free (CVE-ID: CVE-2025-68745)

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 perform a denial of service (DoS) attack.

The vulnerability exists due to a double free error within the drivers/scsi/qla2xxx/qla_target.h. 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-2026:67471