CVE-2026-46300: Linux Kernel Missing Initialization of a Variable Vulnerability

Linux Kernel contains a missing initialization of a variable vulnerability that could allow for unintended modification of page-cache-backed data via failure to preserve the shared-fragment marker during socket buffer coalescing, causing ESP input processing to decrypt shared fragments in place.

This vulnerability can be chained with CVE-2026-109618 and CVE-2026-109619 to implant PHP webshells and run commands as root.

Vereiste actie: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable.

Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Deadline (US federaal): 2026-10-31.