Linux Kernel up to 6.12.102/6.18.43/7.1.7/7.2-rc5 Bluetooth iso_sock_timeout/iso_conn_del use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k0.47+

Summaryinfo

A vulnerability identified as very critical has been detected in Linux Kernel up to 6.12.102/6.18.43/7.1.7/7.2-rc5. The affected element is the function iso_sock_timeout/iso_conn_del of the component Bluetooth. This manipulation causes use after free. This vulnerability is tracked as CVE-2026-74535. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.12.102/6.18.43/7.1.7/7.2-rc5 and classified as very critical. Affected by this vulnerability is the function iso_sock_timeout/iso_conn_del of the component Bluetooth. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: avoid deadlocks in iso_sock_timeout iso_sock_timeout() takes lock_sock, so sync disabling the timer while holding that lock may deadlock. iso_sock_timeout() may also run concurrently with iso_conn_del(), which leads to UAF [Task 1] [Task hdev->workqueue] iso_sock_timeout iso_conn_del iso_conn_hold_unless_zero iso_chan_del `------------> iso_conn_put caller frees hcon iso_conn_put iso_conn_free conn->hcon->iso_data = NULL; /* UAF */ Fix the deadlock by removing the disable from the lock_sock sections. Move the timer from iso_conn to iso_pinfo to decouple it from iso_conn which may need to be freed in lock_sock section. Convert some of the clear_timer to disable_timer.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-74535 since 08/15/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/15/2026).

Upgrading to version 6.12.103, 6.18.44, 7.1.8 or 7.2-rc6 eliminates this vulnerability. Applying the patch 16d89a63e08280abeef7218970a3bbd7ca62b021/82e982f54f962f72646868ddbb2c3bd9ea178568/3c3d5f85db80145636bb991a6005e2760012b985/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43 is able to eliminate this problem.

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Productinfo

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Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.12.103/6.18.44/7.1.8/7.2-rc6
Patch: 16d89a63e08280abeef7218970a3bbd7ca62b021/82e982f54f962f72646868ddbb2c3bd9ea178568/3c3d5f85db80145636bb991a6005e2760012b985/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43

Timelineinfo

08/15/2026 Advisory disclosed
08/15/2026 +0 days CVE reserved
08/15/2026 +0 days VulDB entry created
08/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74535 (🔒)
GCVE (CVE): GCVE-0-2026-74535
GCVE (VulDB): GCVE-100-390847

Entryinfo

Created: 08/15/2026 15:37
Changes: 08/15/2026 15:37 (59)
Complete: 🔍
Cache ID: 216::103

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