TI-2026-52316 Aliases CVE-2026-74533 GHSA-xf88-xmxw-hhch

Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero

MEDIUM 40Published 2026-08-15 · Updated 2026-10-21

Key facts

Attack vector: Adjacent network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero hci_conn::iso_data is accessed and modified without lock or RCU. This leads to a race [Task hdev->workqueue] [Task 2] iso_recv iso_conn_put(conn) conn = LOAD hcon->iso_data iso_conn_free(conn) iso_conn_hold_unless_zero(conn) hcon->iso_data = NULL kfree(conn) kref_get_unless_zero(&conn->ref) /* UAF */ and also to races in iso_conn_add() vs. iso_conn_free(). Fix by adding spinlock hci_conn::proto_lock and using it to guard hci_conn::iso_data.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00239 15th percentileScored 2026-11-07

Fix Partial Linux (Linux): 6.12.114, 6.12, 7.1.8 +1Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Linux	Linux	6.12.2 to before 6.12.114; 6.11.11 to before 6.12	6.12.114, 6.12	Patch available	CNA
Linux	Linux	6.13 and later	6.12.114, 7.1.8, 7.2	Patch available	CNA

Linux VendorLinux Affected 6.12.2 to before 6.12.114; 6.11.11 to before 6.12 Fixed in 6.12.114, 6.12 Patch available CNA
Linux VendorLinux Affected 6.13 and later Fixed in 6.12.114, 7.1.8, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:o:linux:linux_kernel::::::::	—	—	Linux

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Fix · CNA Linux (Linux) Fixed in 6.12.114, 6.12
Fix · CNA Linux (Linux) Fixed in 6.12.114, 7.1.8, 7.2

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 10	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 6	Affected	No fix planned: Out of support scope
Red Hat Enterprise Linux 9	Affected	No fix yet: Fix deferred

Not affected: 3 products

Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9

Timeline

2026-10-02 Threatist record created from CVE-2026-74533
2026-10-03 Alias added: GHSA-xf88-xmxw-hhch
2026-10-18 CISA SSVC decision points changed
2026-10-18 Priority changed: LOW → MEDIUM
2026-10-18 Priority changed: MEDIUM → LOW
2026-10-21 Fix available: Linux/Linux@08ac98f18c8d24cc037858dd6fba2670155e4e84, Linux/[email protected] · CNA
2026-10-21 1 new reference · CNA
2026-10-23 Priority changed: LOW → MEDIUM
2026-10-26 Affected versions changed · Red Hat
2026-10-26 CVSS score changed · Red Hat
2026-10-29 Affected versions changed · Red Hat

References

Other 3

TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4

See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences