CVE-2025-39861 [High] | Use-After-Free in Linux Kernel

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.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-09-20	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-09-20

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.8	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.9	[email protected]
7.8	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.9	134c704f-9b21-4f2e-91b3-4a467353bcc0

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.8

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.9

[email protected]

7.8

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.9

134c704f-9b21-4f2e-91b3-4a467353bcc0

OS Trackers for CVE-2025-39861

vendor	priority	summary	link
`debian`	unimportant	CVE-2025-39861 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2025-39861
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2025-39861
`suse`	medium	CVE-2025-39861 severity moderate: SUSE including 469 source package names (2.1.3-6.80:kernel-default-base-6.4.0-35.1.21.12, 2.1.3-7.57:kernel-default-6.4.0-35.1, …), 1064 product×package rows across 212 product lines (Container suse/sl-micro/6.0/base-os-container, Container suse/sl-micro/6.0/kvm-os-container, … (212 product lines)): Fixed 619, Known Affected 231, Known Not Affected 193, First Fixed 21.	https://www.suse.com/security/cve/CVE-2025-39861/
`ubuntu`	medium	CVE-2025-39861 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1414 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1017, ignored 176, released 117, not-affected 95, needed 5, needs-triage 2, pending 2.	https://ubuntu.com/security/CVE-2025-39861

Affected software / configurations for CVE-2025-39861

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 6.4, < 6.6.105	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.7, < 6.12.46	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.13, < 6.16.6	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.17	cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::
linux	linux_kernel	6.17	cpe:2.3:o:linux:linux_kernel:6.17:rc2::::::
linux	linux_kernel	6.17	cpe:2.3:o:linux:linux_kernel:6.17:rc3::::::
linux	linux_kernel	6.17	cpe:2.3:o:linux:linux_kernel:6.17:rc4::::::

References for CVE-2025-39861

URL	Tags
https://git.kernel.org/stable/c/1503756fffe76d5aea2371a4b8dee20c3577bcfd	Patch
https://git.kernel.org/stable/c/28010791193a4503f054e8d69a950ef815deb539	Patch
https://git.kernel.org/stable/c/7cc08f2f127b9a66f46ea918e34353811a7cb378	Patch
https://git.kernel.org/stable/c/bd75eba88e88d7b896b0c737b02a74a12afc235f	Patch

URL

CVE-2025-39861 | Bluetooth: vhci: Prevent use-after-free by removing debugfs files early

Exploit prediction scoring system (EPSS) score for CVE-2025-39861

Common vulnerability scoring system (CVSS) metrics for CVE-2025-39861

Weakness enumeration for CVE-2025-39861

OS Trackers for CVE-2025-39861

Affected software / configurations for CVE-2025-39861

References for CVE-2025-39861