Published Apr 11, 2023Sources checked Oct 29, 2026
7.5HIGHCVSS out of 10
What this means
Review the available evidence
CVE-2023-26964 and is rated High severity with a CVSS score of 7.5. 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: Aug 12, 2026
Vendor remediation details
CBL-Mariner Releases
Vendor-listed releases
2024.4-1
h2-0.3.26
3.2.0.azl0-1
2022.1-7
3.2.0.azl0-2
CISA KEVNot listedBased on the latest collected catalog
EPSS1.1%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2023-26964?
An issue was discovered in hyper v0.13.7. h2-0.2.4 Stream stacking occurs when the H2 component processes HTTP2 RST_STREAM frames. As a result, the memory and CPU usage are high which can lead to a Denial of Service (DoS).