CVE Intelligence
High

CVE-2026-90001 — HID: bpf: serialize device reference release in struct_ops destroy path

In the Linux kernel, the following vulnerability has been resolved: HID: bpf: serialize device reference release in struct_ops destroy path __hid_bpf_ops_destroy_device() and hid_bpf_unreg() can race on the same registration reference, double-putting struct hid_device and freeing it while hid_destroy_device() still uses it. Serialize the remove/NULL decision under hdev->bpf.prog_list_lock so exactly one path releases each registration reference: unreg re-checks ops->hdev under the lock and returns without putting when the destroy path already cleared it; all put_device() calls happen after the lock is dropped, which is safe because a concurrent unreg then observes ops->hdev == NULL under the lock. Background: each successful attach (hid_bpf_ops_reg) acquires one device reference (hid_get_device()). Two paths can release it: - device destruction: hid_destroy_device() -> hid_bpf_destroy_device() -> __hid_bpf_ops_destroy_device(), which walks hdev->bpf.prog_list under rcu_read_lock() and drops one reference per attached program; - BPF link release: bpf map delete (no BPF_F_LINK) synchronously calls st_ops->unreg() -> hid_bpf_unreg(), which drops the reference for its own registration. The coordination handshake (e->hdev = NULL on the destroy side vs "if (!hdev) return" on the unreg side) is a TOCTOU check: the two paths run under different lock domains (rcu_read_lock vs prog_list_lock), so a concurrent unreg can read ops->hdev as non-NULL, block on prog_list_lock, and then proceed while the destroy traversal executes - both paths then drop the same reference. The refcount reaches zero legitimately (each decrement is individually valid), so no refcount_t saturation fires: the device is simply freed while the transport is still inside hid_destroy_device(), and subsequent teardown touches freed memory. The fix serializes the remove/NULL decision under prog_list_lock on both sides and moves the destroy-side puts outside the lock. With the lock held, plain reads/writes of ops->hdev are sufficient; no READ_ONCE/WRITE_ONCE are added, keeping the patch minimal. Unlocked-read safety: the unlocked read of ops->hdev at the top of hid_bpf_unreg() cannot touch a freed device, because the unreg path itself still holds this registration's reference (released only by its own hid_put_device() after the lock is dropped), and a destroy traversal that already cleared ops->hdev makes the lock-internal re-check return early without any put. At most one of the two paths releases each registration reference.

Published Sep 16, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

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
  • Technical severity (high)+6

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
—
No EPSS score.
Affects
Linux
Linux
CVSS base
7.8
High · 2 source(s)

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.

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

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ ebc0d8093e8c97de459615438edefad1a4ac352c and < 401359684620145be710de97b87e1a47abfe1459≥ ebc0d8093e8c97de459615438edefad1a4ac352c and < c7f927aa8b55008ed5ea0814313d5dad771dcf3c≥ ebc0d8093e8c97de459615438edefad1a4ac352c and < bfb7939788f3c8dd080a4dd81e38d625b35d194e≥ ebc0d8093e8c97de459615438edefad1a4ac352c and < 9cdc7e6dc7a99ad7311ad5e7c145f2b9ce4e24b0version 6.11 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.8 CVSS 3.1 High 1.8 5.9 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
7.8 CVSS 3.1 High — — Linux via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67)

Detection

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

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · linux/linux
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • CVSS changed · 7.8
    Oct 15, 2026 · NIST National Vulnerability Database
  • 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
    Sep 16, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

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

References

4 on the record

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

  • CVE-2026-99999 ipv4: validate checksum_start before completing checksum 14h
  • CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 14h
  • CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
  • CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
  • CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
  • CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d

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 FIRST EPSS score.
  • 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-2026-90001 is "HID: bpf: serialize device reference release in struct_ops destroy path", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. 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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