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CVE-2026-74508 Linux kernel CVE debrief

The Linux kernel has a vulnerability in the Bluetooth HIDP component. An attacker can send an empty basic-mode SDU to cause the use of an uninitialized byte from the skb tailroom, potentially leading to undefined behavior. This vulnerability, CVE-2026-74508, affects the Linux kernel's Bluetooth HIDP implementation, allowing for potential remote code execution. The issue arises from the HIDP protocol's failure to properly handle empty basic-mode SDUs, which can cause the use of uninitialized memory. To mitigate this vulnerability, users should apply the official patch from the Linux kernel repository and review their Bluetooth HIDP configurations. Additionally, monitoring for suspicious activity and reviewing compensating controls for exposed systems is recommended. The vulnerability has been resolved in the Linux kernel, and the patch is available. However, the exact impact and affected scope are still being reviewed. Defenders should verify the affected systems and apply the patch or mitigations as soon as possible.

Vendor
Linux kernel
Product
Linux kernel
CVSS
HIGH 8.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-15
Original CVE updated
2026-08-23
Advisory published
2026-08-15
Advisory updated
2026-08-23

Who should care

Linux kernel developers, administrators, and users of Bluetooth HIDP devices should be aware of this vulnerability and take necessary actions to mitigate it. They should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. They should also plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Technical summary

The Linux kernel's Bluetooth HIDP component is vulnerable to an attack where an empty basic-mode SDU can be sent to cause the use of an uninitialized byte from the skb tailroom. This can lead to undefined behavior and potentially allow for remote code execution. The vulnerability has been resolved in the Linux kernel, and the patch is available. The control path produces two reports and the interrupt path produces one. The byte can also be controlled by a malformed lower-layer packet.

Defensive priority

High priority due to potential for remote code execution

Recommended defensive actions

  • Apply the patch from the Linux kernel repository
  • Review and update Bluetooth HIDP configurations
  • Monitor for suspicious activity
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The evidence for this CVE is based on official CVE and NVD records, as well as source references from the Linux kernel repository. The vulnerability has been resolved in the Linux kernel, and the patch is available. However, the exact impact and affected scope are still being reviewed. Defenders should verify the affected systems and apply the patch or mitigations as soon as possible. The CVE record was published on 2026-08-15T13:17:55.843Z and has not been modified since then. Additional review of the Linux kernel patch reference and other source references is recommended.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-08-15T13:17:55.843Z and has not been modified since then.