- Published
- Source
- SecurityWeek
- Filed under
- Zero-days, Microsoft, Malware & exploits
It abuses CLFS and Windows Defender to trigger arbitrary file creation in the context of the antimalware process.
If you run the affected product
- Find every instance – especially the ones reachable from the internet.
- Apply the vendor's patch or mitigation now: exploited flaws are fixed in days, not at the next patch cycle.
- Then check for signs it was used before you patched: web shells, new accounts, unusual outbound traffic.
More helpCISA's Known Exploited Vulnerabilities catalogue (opens in a new tab)
Defender’s notebook
The attacker technique behind this story, in MITRE’s terms – and what to check in your own estate.
Exploit Public-Facing Application
Initial AccessWhat a defender checks
- Find every internet-facing instance of the affected product.
- Patch, or apply the vendor's mitigation now – CISA's KEV list gives a deadline.
- Look for signs it was exploited before you patched: web shells, new accounts, odd outbound traffic.
Build the skillBlue Team Analyst, Vulnerability Management
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