CVE-2026-46300
Linux Kernel: Out-of-bounds Write
- Act
- CVSS 7.8 High
- CISA KEV, due
- VulnCheck KEV
- ENISA exploited-vulnerability catalog
What it is
ReportedLinux 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.
Dates
What is affected
ReportedLinux; Kernel. Product-level identification only; no affected-version conclusion is available from this field.
Dates
Urgency and basis
Tracker computedAct
Current priority score and EPSS: loading from the tracker record. They are read when this page loads and are not shown without JavaScript. They change daily and are not part of "Source last updated".
Dates
Exploitation evidence
Reportedlisted by a tracked exploitation catalog · CISA KEV · VulnCheck KEV · ENISA exploited-vulnerability catalog
Dates
What to do
ReportedApply 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.
Source remediation ↗Dates
Detection and validation
Mapped metadata availability only. These signals do not change priority.
Sigma
Not mapped by tracked sources.
Atomic
Not mapped by tracked sources.
Nuclei
Not mapped by tracked sources.
Evidence detail
Loading the full tracker evidence record…