Riskcovery

CVE-2026-74533

Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero

State
Published
Severity
8.8 High
Published
Aug 15, 2026
Updated
Oct 21, 2026
Reserved
Aug 15, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.18.8 HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLinux

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • a58d0f5dac322e16cc75334d000666512341bde5 to before 08ac98f18c8d24cc037858dd6fba2670155e4e84Affected
  • dc26097bdb864a0d5955b9a25e43376ffc1af99b to before 876a3e94c70d0859d1dad1c986112d4f0d99eba8Affected
  • dc26097bdb864a0d5955b9a25e43376ffc1af99b to before af24e338bf5dafb80f42baa9a0b9e9b57b1c5d9cAffected
  • f53e7489273dc2bb307bf50f319b3762d45534f0Affected
  • 6.12.2 to before 6.12.114Affected
  • 6.11.11 to before 6.12Affected
LinuxLinux
  • 6.13Affected
  • before 6.13Not affected
  • 6.12.114 through 6.12.*Not affected
  • 7.1.8 through 7.1.*Not affected
  • 7.2 and laterNot affected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.