Linux Kernel up to 6.1.158/6.6.116/6.12.58/6.17.8 Bluetooth mesh_send_done use after free

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.1.158/6.6.116/6.12.58/6.17.8. This impacts the function mesh_send_done of the component Bluetooth. Such manipulation leads to use after free. This vulnerability is referenced as CVE-2025-40284. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.1.158/6.6.116/6.12.58/6.17.8. Affected by this issue is the function mesh_send_done of the component Bluetooth. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: cancel mesh send timer when hdev removed mesh_send_done timer is not canceled when hdev is removed, which causes crash if the timer triggers after hdev is gone. Cancel the timer when MGMT removes the hdev, like other MGMT timers. Should fix the BUG: sporadically seen by BlueZ test bot (in "Mesh - Send cancel - 1" test). Log: ------ BUG: KASAN: slab-use-after-free in run_timer_softirq+0x76b/0x7d0 ... Freed by task 36: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __kasan_save_free_info+0x3a/0x60 __kasan_slab_free+0x43/0x70 kfree+0x103/0x500 device_release+0x9a/0x210 kobject_put+0x100/0x1e0 vhci_release+0x18b/0x240 ------

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2025-40284 since 04/16/2025. The exploitation is known to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/23/2026).

The vulnerability scanner Nessus provides a plugin with the ID 277720 (Linux Distros Unpatched Vulnerability : CVE-2025-40284), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.159, 6.6.117, 6.12.59 or 6.17.9 eliminates this vulnerability. Applying the patch 990e6143b0ca0c66f099d67d00c112bf59b30d76/2927ff643607eddf4f03d10ef80fe10d977154aa/7b6b6c077cad0601d62c3c34ab7ce3fb25deda7b/fd62ca5ad136dcf6f5aa308423b299a6be6f54ea/55fb52ffdd62850d667ebed842815e072d3c9961 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (277720), EUVD (EUVD-2025-201571) and CERT Bund (WID-SEC-2025-2756). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• NetApp FAS
• NetApp AFF
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• Microsoft Azure Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.158
• 6.6.116
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5
• 6.17.6
• 6.17.7
• 6.17.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

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