Published Sep 16, 2026Sources checked Nov 10, 2026
N/ACVSS not listedScore unavailable
What this means
Review the available evidence
CVE-2026-89878. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: Oct 21, 2026
Release Notes
Vendor-listed releases
6.6.157.1-1
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-2026-89878?
In the Linux kernel, the following vulnerability has been resolved:
media: s2255: check firmware size before reading trailing marker
s2255_probe() reads a 4-byte marker and version from the last 8 bytes of the firmware blob (fw->data[fw_size - 8] and [fw_size - 4]). If the firmware file is shorter than 8 bytes, fw_size - 8 underflows and the access reads out of bounds.