Summary
| Parameter | Value |
|---|---|
| CVE ID | CVE-2026-53266 |
| Alert Source | CISA KEV - Active Exploitation |
| CVE Publication Year | 2026 |
| Date Published | 2026-09-18 |
| Vendor | Linux |
| Product | Kernel |
| CVSS Score | 8.8 (high) |
| EPSS Score | 0.3% (percentile: 20%) |
| CISA KEV | Yes - confirmed active exploitation |
| Ransomware | Not confirmed |
| Remediation Deadline | 2026-09-21 |
Vulnerability Description
Linux Kernel contains an out-of-bounds write vulnerability in the ebtables SNAT target which allows an ARP sender hardware address rewrite to write directly into a nonlinear socket-buffer fragment backed by a splice-imported file page. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.
Required Actions
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.
Who Is Affected?
This vulnerability affects Kernel by Linux. Check if your organization uses this software and requires updates.
Sources
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