CVE-2026-98730 Linux CVE debrief

Who should care

Linux kernel maintainers, Bluetooth developers, and system administrators responsible for Linux systems with Bluetooth capabilities should assess exposure and apply kernel updates as needed.

Why it matters

This vulnerability in the Linux kernel's Bluetooth component can lead to potential buffer overflows, data corruption, and system instability. Linux kernel maintainers, Bluetooth developers, and system administrators should assess exposure and apply kernel updates as needed to prevent potential issues.

• Potential buffer overflow and data corruption
• Possible denial-of-service (DoS) due to system instability
• Code execution may be possible but requires further verification

Technical summary

The btintel_pcie_send_frame() function in the Linux kernel's Bluetooth component does not properly validate packet sizes, allowing an oversized packet to overflow a fixed-size DMA buffer. This issue can be exploited by a user-space process with HCI_CHANNEL_USER access, potentially causing a buffer overflow and system instability. The vulnerability arises from the btintel_pcie_send_frame() function, which copies data into a fixed BTINTEL_PCIE_BUFFER_SIZE (4096) DMA buffer. A 4-byte PCIe type header is prepended to the packet during the copy process.

Defensive priority

Medium

Recommended defensive actions

• Review and apply kernel updates to ensure the btintel_pcie fix is included
• Restrict HCI_CHANNEL_USER access to trusted user-space processes
• Monitor system logs for potential buffer overflow indicators
• Verify HCI_CHANNEL_USER access controls are in place
• Check for and apply any additional vendor-provided patches or mitigations
• Track and review system stability and performance post-update
• Confirm affected product deployments exist in managed environments

Evidence notes

The CVE record and NVD entry provide details about the vulnerability. However, the scope of affected systems and potential impact require further verification from official sources. A user-space process with HCI_CHANNEL_USER access can inject an oversized packet and overflow the buffer. The btintel_pcie_send_frame() function eventually copies skb->data into a fixed BTINTEL_PCIE_BUFFER_SIZE (4096) DMA buffer via memcpy() in btintel_pcie_prepare_tx(), with a 4-byte PCIe type header prepended.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.