CVE-2025-38736 | net: usb: asix_devices: Fix PHY address mask in MDIO bus initialization

In the Linux kernel, the following vulnerability has been resolved: net: usb: asix_devices: Fix PHY address mask in MDIO bus initialization Syzbot reported shift-out-of-bounds exception on MDIO bus initialization. The PHY address should be masked to 5 bits (0-31). Without this mask, invalid PHY addresses could be used, potentially causing issues with MDIO bus operations. Fix this by masking the PHY address with 0x1f (31 decimal) to ensure it stays within the valid range.

Published: 2025-09-05 Last update: 2026-05-12 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2025-38736 is rated Low Risk (30.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-38736

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-09-06 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-38736

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.1 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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:H)
Serious risk that confidential data gets exposed in a big 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 5.2 [email protected]

Weakness enumeration for CVE-2025-38736

GitHub Security Advisory for CVE-2025-38736

GHSA-9pqv-7h63-32cr · Severity: high — In the Linux kernel, the following vulnerability has been resolved: net: usb: asix_devices: Fix...

OS Trackers for CVE-2025-38736

vendor priority summary link
debian unimportant CVE-2025-38736 unimportant 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-2025-38736
redhat https://access.redhat.com/security/cve/CVE-2025-38736
suse medium CVE-2025-38736 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-2025-38736/
ubuntu medium CVE-2025-38736 medium priority: Ubuntu including 144 source packages (linux, linux-allwinner-5.19, …), 1152 status rows across 8 suites (bionic, focal, jammy, noble, plucky, trusty, upstream, xenial): DNE 797, ignored 157, not-affected 124, released 74. https://ubuntu.com/security/CVE-2025-38736

Affected software / configurations for CVE-2025-38736

Vendor Product Version Raw CPE
linux linux_kernel >= 6.15.11, < 6.16 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.16.2, < 6.16.4 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 6.12.43 cpe:2.3:o:linux:linux_kernel:6.12.43:*:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2025-38736

cvelogic Threat Intelligence