CVE-2026-31688 | driver core: enforce device_lock for driver_match_device()

In the Linux kernel, the following vulnerability has been resolved: driver core: enforce device_lock for driver_match_device() Currently, driver_match_device() is called from three sites. One site (__device_attach_driver) holds device_lock(dev), but the other two (bind_store and __driver_attach) do not. This inconsistency means that bus match() callbacks are not guaranteed to be called with the lock held. Fix this by introducing driver_match_device_locked(), which guarantees holding the device lock using a scoped guard. Replace the unlocked calls in bind_store() and __driver_attach() with this new helper. Also add a lock assertion to driver_match_device() to enforce this guarantee. This consistency also fixes a known race condition. The driver_override implementation relies on the device_lock, so the missing lock led to the use-after-free (UAF) reported in Bugzilla for buses using this field. Stress testing the two newly locked paths for 24 hours with CONFIG_PROVE_LOCKING and CONFIG_LOCKDEP enabled showed no UAF recurrence and no lockdep warnings.

Published: 2026-04-27 Last update: 2026-05-06 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2026-31688 is rated Low Risk (32.9/100): 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-2026-31688

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 2026-04-28 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-31688

CVSS metrics for this CVE.

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]

Weakness enumeration for CVE-2026-31688

GitHub Security Advisory for CVE-2026-31688

GHSA-cxv6-chw7-mhrh · Severity: high — In the Linux kernel, the following vulnerability has been resolved: driver core: enforce...

OS Trackers for CVE-2026-31688

vendor priority summary link
debian not yet assigned CVE-2026-31688 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-31688
redhat medium https://access.redhat.com/security/cve/CVE-2026-31688
suse medium https://www.suse.com/security/cve/CVE-2026-31688/
ubuntu medium CVE-2026-31688 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 173, needed 130, released 83, not-affected 10, needs-triage 5. https://ubuntu.com/security/CVE-2026-31688

Affected software / configurations for CVE-2026-31688

Vendor Product Version Raw CPE
linux linux_kernel >= 2.6.30, < 7.0 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2026-31688

cvelogic Threat Intelligence