CVE-2026-33825: Microsoft Defender Antimalware Platform · Insufficient Granularity of Access Control
Affects Microsoft Defender Antimalware PlatformSource CVE Database V5
Exploited in the wild · used in ransomware campaigns · KEV due 6 May 2026 · public exploit available · 6% EPSS : upgrade to 4.18.26030.3011 now.
Data as of 30 Oct 2026, 11:34 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates
- Ransomware
- Used in ransomware campaigns
- EPSS
- 6.7% chance of exploitation in 30 days – higher than 93% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.18.26030.3011
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:CExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 14 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
Public exploit code: GitHub proofs of concept
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 8 days after disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by Microsoft Corporation
, 21 days before disclosure
CVE published
on cve.org
, t = 0
In Threat Radar
record ingested
, 35 minutes after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed · ransomware use known
, 8 days after disclosure
KEV remediation due
US federal deadline
, 22 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), GitHub proofs of concept, CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 24 Oct 2026.
What to do
Upgrade Microsoft Defender Antimalware Platform to 4.18.26030.3011.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MicrosoftMicrosoft Defender Antimalware Platform | Affected
| Fixed in
|
Description
CVE-2026-33825 is a high-severity vulnerability in Microsoft Defender Antimalware Platform caused by insufficient granularity of access control. It allows an authorized local attacker to elevate privileges. The vulnerability affects versions from 4.0.0.0 up to but not including 4.18.26030.3011. Exploits are known in the wild, including use in ransomware campaigns. An official fix is available from Microsoft.