CVE-2026-98581 Linux CVE debrief

Who should care

Linux system administrators, security teams, and developers should assess exposure and apply patches to prevent potential memory exhaustion or DoS via leaked kernel sockets. Linux kernel developers and maintainers should review and test patches to ensure vulnerability is properly addressed. Users of Linux-based systems should be aware of potential risks and take steps to mitigate them.

Why it matters

This vulnerability in the Linux kernel's NFC LLCP implementation can lead to memory exhaustion or DoS via leaked kernel sockets, requiring Linux system administrators and security teams to assess exposure and apply patches.

• Memory exhaustion or DoS via leaked kernel sockets.
• Potential disruption of Linux-based systems.

Technical summary

The Linux kernel's NFC LLCP implementation has a vulnerability that can lead to list corruption and refcount desync. This allows an unprivileged local process to drive memory exhaustion or DoS via leaked kernel sockets by handling DM(NOBOUND)/DM(REJ) for a socket still linked on local->connecting_sockets. The vulnerability arises from improper handling of sockets in the LLCP implementation, leading to a use-after-free race condition. The issue can be mitigated by applying patches to the Linux kernel, which address the improper handling of sockets and prevent the use-after-free race condition.

Defensive priority

Apply patch or update Linux kernel to prevent potential memory exhaustion or DoS via leaked kernel sockets.

Recommended defensive actions

• Review Linux kernel configurations and apply patches to prevent potential memory exhaustion or DoS via leaked kernel sockets.
• Inventory Linux systems for NFC LLCP usage and assess exposure.
• Monitor Linux kernel updates and apply patches promptly.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• technicalSummary

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but do not specify versions, exploitation, impact, or remediation beyond applying patches. The Linux kernel's NFC LLCP implementation has a vulnerability that can lead to list corruption and refcount desync. This allows an unprivileged local process to drive memory exhaustion or DoS via leaked kernel sockets by handling DM(NOBOUND)/DM(REJ) for a socket still linked on local->connecting_sockets. Evidence is based on the CVE record, NVD entry, and Linux kernel patch.

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.