CVE-2026-33825 — Defender Antimalware Platform
HIGHCVE-2026-33825 is a high-severity (CVSS 7.8) CWE-1220 vulnerability in microsoft defender antimalware platform. It is in CISA's Known Exploited Vulnerabilities catalog (added 2026-04-22) and has been used in ransomware campaigns — treat it as actively exploited and patch now. A fix is available — see the affected versions and patch details below.
Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2026-04-22 — including use in ransomware campaigns. Federal agencies were required to remediate by 2026-05-06.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2026-33825.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-33825 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Description
Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.
Affected Products
defender antimalware platformmicrosoftResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Vendor / applianceDetect
Inventory every microsoft defender antimalware platform deployment and check each version against the affected-products list above.
Fix
Apply the microsoft defender antimalware platform security patch or hotfix for CVE-2026-33825 on the affected version, following the vendor advisory for your exact build.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2026-33825 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.