CVE-2025-39876 [Medium] | Security Vulnerability in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: net: fec: Fix possible NPD in fec_enet_phy_reset_after_clk_enable() The function of_phy_find_device may return NULL, so we need to take care before dereferencing phy_dev.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-01-21	0.07%	0.03%	-0.04%
2	2025-12-18	0.02%	0.07%	+0.05%
3	2025-09-23	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-01-21

0.07%

0.03%

-0.04%

2025-12-18

0.02%

0.07%

+0.05%

2025-09-23

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.5	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	3.6	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.5

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

3.6

[email protected]

OS Trackers for CVE-2025-39876

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2025-39876 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6.	https://security-tracker.debian.org/tracker/CVE-2025-39876
`redhat`	—	—	https://access.redhat.com/security/cve/CVE-2025-39876
`suse`	medium	CVE-2025-39876 severity moderate: SUSE including 483 source package names (13.2-6.19:libjitterentropy3-3.4.1-3.1, 13.2-6.19:libopenssl3-3.1.4-6.1, …), 1022 product×package rows across 212 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (212 product lines)): Fixed 740, Known Affected 231, Known Not Affected 30, First Fixed 21.	https://www.suse.com/security/cve/CVE-2025-39876/
`ubuntu`	medium	CVE-2025-39876 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 148, not-affected 40, needed 28, pending 3, needs-triage 2.	https://ubuntu.com/security/CVE-2025-39876

Affected software / configurations for CVE-2025-39876

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 4.19.153, < 4.20	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.4.73, < 5.4.300	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.8.17, < 5.9	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.9.2, < 5.10.245	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.194	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 6.1.153	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.2, < 6.6.107	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.7, < 6.12.48	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.13, < 6.16.8	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::::::
linux	linux_kernel	6.17	cpe:2.3:o:linux:linux_kernel:6.17:rc5::::::
debian	debian_linux	11.0	cpe:2.3:o:debian:debian_linux:11.0:::::::*

References for CVE-2025-39876

URL	Tags
https://git.kernel.org/stable/c/03e79de4608bdd48ad6eec272e196124cefaf798	Patch
https://git.kernel.org/stable/c/20a3433d31c2d2bf70ab0abec75f3136b42ae66c	Patch
https://git.kernel.org/stable/c/4fe53aaa4271a72fe5fe3e88a45ce01646b68dc5	Patch
https://git.kernel.org/stable/c/5f1bb554a131e59b28482abad21f691390651752	Patch
https://git.kernel.org/stable/c/8c60d12bba14dc655d2d948b1dbf390b3ae39cb8	Patch
https://git.kernel.org/stable/c/93a699d6e92cfdfa9eb9dbb8c653b5322542ca4f	Patch
https://git.kernel.org/stable/c/eb148d85e126c47d65be34f2a465d69432ca5541	Patch
https://git.kernel.org/stable/c/fe78891f296ac05bf4e5295c9829ef822f3c32e7	Patch
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html	Mailing List Third Party Advisory

URL

CVE-2025-39876 | net: fec: Fix possible NPD in fec_enet_phy_reset_after_clk_enable()

Exploit prediction scoring system (EPSS) score for CVE-2025-39876

Common vulnerability scoring system (CVSS) metrics for CVE-2025-39876

Weakness enumeration for CVE-2025-39876

OS Trackers for CVE-2025-39876

Affected software / configurations for CVE-2025-39876

References for CVE-2025-39876