CVEs / CVE-2026-33825
CVE-2026-33825: Microsoft Defender Insufficient Granularity of Access Control Vulnerability
- Known exploited in the CISA KEV catalog since 22 Apr 2026
- high 7.8 CVSS 3.1 (from the CNA)
- EPSS 6.74% chance of exploitation in the next 30 days, higher than 93% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Microsoft Defender contains an insufficient granularity of access control vulnerability that could allow an authorized attacker to escalate privileges locally.
Description
Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Microsoft Defender Antimalware Platform | from 4.0.0.0, before 4.18.26030.3011 | 4.18.26030.3011 |
Exploitation
| In CISA KEV since | 22 Apr 2026 |
|---|---|
| Due date for US federal agencies | 6 May 2026 |
| Used in ransomware campaigns | Known |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 7.8 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-1220 |
References
- CVE-2026-33825 on NVD
- CVE-2026-33825 in the CISA KEV catalog
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33825 (cited by CISA)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33825 Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-33825 US Government Resource
- https://www.huntress.com/blog/nightmare-eclipse-intrusion Third Party Advisory
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.