CVE-2026-120454 and is rated Medium severity with a CVSS score of 5.5. 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: Nov 7, 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-2026-120454?
The Sleuth Kit through 4.15.0 contains a NULL pointer dereference vulnerability in decmpfs_decompress_lzvn_attr() that allows attackers to crash the tool by supplying a crafted HFS+ image. Attackers can set a huge uncompressed_size in an LZVN inline com.apple.decmpfs attribute so allocation fails and the decoder writes through NULL, causing denial of service.