Published Oct 15, 2026Sources checked Oct 21, 2026
6.1MEDIUMCVSS out of 10
What this means
Review the available evidence
CVE-2026-111137 and is rated Medium severity with a CVSS score of 6.1. 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 17, 2026
Release Notes
CISA KEVNot listedBased on the latest collected catalog
EPSS0.1%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-111137?
libsmi through 0.5.0 contains an out-of-bounds write vulnerability in smiValueAsString() in lib/smi.c that allows attackers to overflow a fixed 1024-byte static buffer through hex rendering of OCTET STRING values. Attackers can supply a crafted MIB with an OCTET STRING DEFVAL of 512 or more octets and a leading 0x00 byte to corrupt adjacent library globals and crash smidump or other consumers.