Published Jun 16, 2025Sources checked Nov 11, 2026
9.1CRITICALCVSS out of 10
What this means
Review the available evidence
CVE-2025-49796 and is rated Critical severity with a CVSS score of 9.1. 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: Aug 13, 2026
CBL-Mariner Releases
Vendor-listed releases
2.10.4-8
2.11.5-6
CISA KEVNot listedBased on the latest collected catalog
EPSS1.6%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2025-49796?
A vulnerability was found in libxml2. Processing certain sch:name elements from the input XML file can trigger a memory corruption issue.
This flaw allows an attacker to craft a malicious XML input file that can lead libxml to crash, resulting in a denial of service or other possible undefined behavior due to sensitive data being corrupted in memory.