CVE-2026-99050 Linux CVE debrief

Who should care

Defenders responsible for Linux kernel deployments should assess exposure and prioritize patching affected versions. They must verify affected versions and patch or update accordingly, and perform inventory checks and monitoring to detect potential exploitation attempts. This includes operators, platform administrators, vulnerability management teams, and security teams who need to ensure the stability and security of their Linux kernel-based systems.

Why it matters

Defenders should prioritize patching affected Linux kernel versions to prevent potential use-after-free conditions. This vulnerability may lead to system crashes or instability, and successful exploitation may allow local attackers to escalate privileges. Defenders must verify affected versions and patch or update accordingly, and perform inventory checks and monitoring to detect potential exploitation attempts.

• Potential use-after-free conditions may lead to system crashes or instability
• Successful exploitation may allow local attackers to escalate privileges
• Defenders must verify affected versions and patch or update accordingly
• Inventory checks and monitoring are necessary to detect potential exploitation attempts

Technical summary

The gpio: mpsse driver in the Linux kernel has a use-after-free vulnerability when arming the IRQ poll worker. This occurs because gpio_mpsse_irq_enable() arms the poll worker before publishing it, which can lead to a use-after-free condition if gpio_mpsse_disconnect() walks the list of workers before they are published. The vulnerability can cause the USB core to free the mpsse_priv structure while the gpio_mpsse_poll() work still accesses it, potentially leading to system crashes or instability. Successful exploitation may allow local attackers to escalate privileges.

Defensive priority

Defenders should prioritize patching affected Linux kernel versions to prevent potential use-after-free conditions.

Recommended defensive actions

• Patch affected Linux kernel versions
• Review and update inventory of Linux kernel deployments
• Monitor for potential use-after-free conditions
• 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.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record and source item provide details about the vulnerability, including its description, affected versions, and references to source code changes. The gpio: mpsse driver in the Linux kernel has a use-after-free vulnerability when arming the IRQ poll worker. This occurs because gpio_mpsse_irq_enable() arms the poll worker before publishing it, which can lead to a use-after-free condition if gpio_mpsse_disconnect() walks the list of workers before they are published. The vulnerability may lead to system crashes or instability,

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.