Unknown

CVE-2026-80660 — hwmon: (occ) unregister sysfs devices outside occ lock

In the Linux kernel, the following vulnerability has been resolved: hwmon: (occ) unregister sysfs devices outside occ lock occ_active(false) and occ_shutdown() unregister sysfs-backed devices while occ->lock is held. hwmon_device_unregister() and sysfs_remove_group() can wait for active sysfs callbacks to drain, and those callbacks can enter the OCC update path and try to take occ->lock again. That gives the unregister paths the lock ordering occ->lock -> sysfs callback drain, while a callback has the opposite edge sysfs callback -> occ->lock. This issue was found by our static analysis tool and then manually reviewed against the current tree. The grounded PoC kept the real unregister and callback carrier: occ_shutdown() hwmon_device_unregister() occ_show_temp_1() occ_update_response() Lockdep reported the circular dependency with occ_shutdown() already holding the OCC mutex and hwmon_device_unregister() waiting on the sysfs side: WARNING: possible circular locking dependency detected ... (sysfs_lock) ... at: hwmon_device_unregister+0x12/0x30 [vuln_msv] ... (&test_occ.lock) ... at: occ_shutdown.constprop.0+0xe/0x40 [vuln_msv] occ_update_response.isra.0+0xb/0x20 [vuln_msv] occ_show_temp_1.constprop.0.isra.0+0x23/0x40 [vuln_msv] *** DEADLOCK *** Serialize hwmon registration and removal with a separate hwmon_lock. Under that lock, detach occ->hwmon and update occ->active while occ->lock is held so concurrent OCC state changes still see a stable state, then drop occ->lock before calling hwmon_device_unregister(). Remove the driver sysfs group before taking occ->lock in occ_shutdown(), so draining the driver attributes cannot wait while the OCC mutex is held. Also make OCC update callbacks return -ENODEV after deactivation, so callbacks that already passed sysfs active protection do not poll the hardware after teardown has detached the hwmon device.

Published Aug 28, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.22%

ahead of 12% of scored CVEs · Oct 26, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 849b0156d9960da628a06756bb920d9571c15e66 and < 2a4c80ff3571498ec6a916273304b6650026b1b0≥ 849b0156d9960da628a06756bb920d9571c15e66 and < e7fd81e9fb1fe476d2131fec66c1138457810ed4≥ 849b0156d9960da628a06756bb920d9571c15e66 and < 2092952f22a7da98e76e84139ae202b1fc7ba899≥ 849b0156d9960da628a06756bb920d9571c15e66 and < f0aad157576da199c146c1bb266442befa7912ca≥ 849b0156d9960da628a06756bb920d9571c15e66 and < 7ee43ec8e6774774abbe9dc3027225e01bc964a5≥ 849b0156d9960da628a06756bb920d9571c15e66 and < e31408734332b8cc611342cdaaab6ba492180156version bc8a32726774286325b0cb0daab55b682cafc1ef≥ 5.15.216 and < 5.16 and 1 more version 5.19	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 26, 2026 · 11 reading(s) · max 0.22%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Aug 28, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

6 on the record

git.kernel.org/stable/c/f0aad157576da199c146c1bb266442befa7912ca
NIST National Vulnerability Database
git.kernel.org/stable/c/7ee43ec8e6774774abbe9dc3027225e01bc964a5
NIST National Vulnerability Database
git.kernel.org/stable/c/e31408734332b8cc611342cdaaab6ba492180156
NIST National Vulnerability Database
git.kernel.org/stable/c/2a4c80ff3571498ec6a916273304b6650026b1b0
NIST National Vulnerability Database
git.kernel.org/stable/c/2092952f22a7da98e76e84139ae202b1fc7ba899
NIST National Vulnerability Database
git.kernel.org/stable/c/e7fd81e9fb1fe476d2131fec66c1138457810ed4
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 21h
Unknown CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 21h
Unknown CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 21h
Unknown CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 21h
Unknown CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 21h
Unknown CVE-2026-99098 dm-integrity: fix buffer overflow in inline mode with large tag size 21h

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-80660 is "hwmon: (occ) unregister sysfs devices outside occ lock", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.22% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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