CVE-2026-64427 — HID: logitech-dj: Fix maxfield check in DJ short report validation
In the Linux kernel, the following vulnerability has been resolved: HID: logitech-dj: Fix maxfield check in DJ short report validation Commit b6a57912854e ("HID: logitech-dj: Prevent REPORT_ID_DJ_SHORT related user initiated OOB write") added validation for the DJ short output report, but the error path dereferences rep->field[0] even when rep->maxfield is zero. Commit 8b9a097eb2fc ("HID: logitech-dj: fix wrong detection of bad DJ_SHORT output report") made the check conditional on rep being present, but a crafted descriptor can still create report ID 0x20 with only padding output items. hid-core registers the report, ignores the padding field, and leaves rep->maxfield as zero. In that case the validation enters the rep->maxfield < 1 branch and then dereferences rep->field[0]->report_count while printing the error message, causing a NULL pointer dereference during probe. This is reproducible with uhid by emulating a Logitech receiver with a padding-only DJ short output report: BUG: KASAN: null-ptr-deref in logi_dj_probe+0xb1/0x754 [hid_logitech_dj] Read of size 4 at addr 0000000000000028 by task kworker/4:1/129 ... Call Trace: logi_dj_probe+0xb1/0x754 [hid_logitech_dj] hid_device_probe+0x329/0x3f0 [hid] really_probe+0x162/0x570 __device_attach+0x137/0x2c0 bus_probe_device+0x38/0xc0 device_add+0xa56/0xce0 hid_add_device+0x19c/0x280 [hid] uhid_device_add_worker+0x2c/0xb0 [uhid] Reject the zero-field report before printing the field report_count.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.1% (30-day exploitation probability)+0
- Technical severity (medium)+3
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.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
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, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 7754ade02d0fb1caf20392baf4e02937378fd136 and < f3790a6af9c7f47d454225cab9dc145270e48f62≥ 2ed9638cfbf9d49bdef9b0f5ee547236c2c2f500 and < 1215febd644c3e16f77e0f1799d89544dd57a754≥ eeb5ad388595ca2b6624689198a057847f3a3e19 and < 6f7f22a8d244c2e586b8eb61c7585784b62aea01≥ 968e84f5c0dca4960580d174500e4bbf0c45dc15 and < 95b3f23d632490b5eb285b9fcf7284f2ac8f9872≥ ce2a731c179df8869e1969a1b2b5b9e4e1c25f8b and < 80c1e18473f63fd7c6a2bc9ad6f3d0a6cc4fb500≥ bc3bba4656ad280267ea78cf845ab6b1d95b9fcd and < 2b70bebc709489d29a31ac2935aeffb8d5228395≥ b6a57912854e7ea36f3b270032661140cc4209cd and < 7a89ad762fad53d56b7002d7ffc923a4b7f4006f≥ b6a57912854e7ea36f3b270032661140cc4209cd and < 590cc4d782487632a52f37c2171bee1eeea29627 and 1 moreversion 7.1 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 7.1 and < 7.1.4version 7.2-rc1version 7.2-rc2 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 5.5 | CVSS 3.1 | Medium | 1.8 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
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.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 5.5
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- git.kernel.org/stable/c/2b70bebc709489d29a31ac2935aeffb8d5228395
- git.kernel.org/stable/c/590cc4d782487632a52f37c2171bee1eeea29627
- git.kernel.org/stable/c/1215febd644c3e16f77e0f1799d89544dd57a754
- git.kernel.org/stable/c/7a89ad762fad53d56b7002d7ffc923a4b7f4006f
- git.kernel.org/stable/c/80c1e18473f63fd7c6a2bc9ad6f3d0a6cc4fb500
- git.kernel.org/stable/c/6f7f22a8d244c2e586b8eb61c7585784b62aea01
- git.kernel.org/stable/c/95b3f23d632490b5eb285b9fcf7284f2ac8f9872
- git.kernel.org/stable/c/f3790a6af9c7f47d454225cab9dc145270e48f62
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 1d
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 1d
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 2d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 2d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 2d
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 2d
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 CISA SSVC assessment.
- 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-2026-64427 is "HID: logitech-dj: Fix maxfield check in DJ short report validation", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.12% 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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