Linux Kernel up to 6.6.104/6.12.45/6.16.5/6.17-rc4 Bluetooth vhci_release use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.6.104/6.12.45/6.16.5/6.17-rc4. This impacts the function vhci_release of the component Bluetooth. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2025-39861. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.6.104/6.12.45/6.16.5/6.17-rc4 and classified as critical. This vulnerability affects the function vhci_release 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: vhci: Prevent use-after-free by removing debugfs files early Move the creation of debugfs files into a dedicated function, and ensure they are explicitly removed during vhci_release(), before associated data structures are freed. Previously, debugfs files such as "force_suspend", "force_wakeup", and others were created under hdev->debugfs but not removed in vhci_release(). Since vhci_release() frees the backing vhci_data structure, any access to these files after release would result in use-after-free errors. Although hdev->debugfs is later freed in hci_release_dev(), user can access files after vhci_data is freed but before hdev->debugfs is released.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2025-39861 since 04/16/2025. The exploitation appears 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 12/22/2025).

The vulnerability scanner Nessus provides a plugin with the ID 265461 (Linux Distros Unpatched Vulnerability : CVE-2025-39861), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.105, 6.12.46, 6.16.6 or 6.17-rc5 eliminates this vulnerability. Applying the patch bd75eba88e88d7b896b0c737b02a74a12afc235f/1503756fffe76d5aea2371a4b8dee20c3577bcfd/7cc08f2f127b9a66f46ea918e34353811a7cb378/28010791193a4503f054e8d69a950ef815deb539 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 (265461) and CERT Bund (WID-SEC-2025-2099). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • Dell Secure Connect Gateway

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

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: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 265461
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39861

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.105/6.12.46/6.16.6/6.17-rc5
Patch: bd75eba88e88d7b896b0c737b02a74a12afc235f/1503756fffe76d5aea2371a4b8dee20c3577bcfd/7cc08f2f127b9a66f46ea918e34353811a7cb378/28010791193a4503f054e8d69a950ef815deb539

Timelineinfo

04/16/2025 CVE reserved
09/19/2025 +156 days Advisory disclosed
09/19/2025 +0 days VulDB entry created
12/22/2025 +94 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39861 (🔒)
GCVE (CVE): GCVE-0-2025-39861
GCVE (VulDB): GCVE-100-325048
CERT Bund: WID-SEC-2025-2099 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/19/2025 18:20
Updated: 12/22/2025 13:12
Changes: 09/19/2025 18:20 (59), 09/23/2025 08:10 (2), 10/20/2025 20:58 (7), 11/12/2025 05:12 (1), 11/29/2025 07:20 (1), 12/13/2025 06:08 (11), 12/22/2025 13:12 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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