Published Sep 17, 2026Sources checked Oct 21, 2026
8.4HIGHCVSS out of 10
What this means
Review the available evidence
CVE-2026-90191 and is rated High severity with a CVSS score of 8.4. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
CISA KEVNot listedBased on the latest collected catalog
EPSS0.2%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-90191?
In the Linux kernel, the following vulnerability has been resolved:
The SBI return value controls how many bytes are copied from shared memory into the RPMI notification buffer. It is not validated against the negotiated shared-memory size before that copy.
The event walker also uses a reversed loop condition and can inspect a short event record.
Validate the complete notification length before copying it, iterate only while a full event header remains, and stop when a declared event payload extends beyond the copied notification data.