VDB-357546 · CVE-2026-33825 · Nessus 306740

Microsoft Defender Antimalware Platform prior 4.18.26030.3011 BlueHammer insufficient granularity of access control

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.3	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical was found in Microsoft Defender Antimalware Platform. This affects an unknown part. The manipulation results in insufficient granularity of access control. This vulnerability is identified as CVE-2026-33825. The attack is only possible with local access. Additionally, an exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, was found in Microsoft Defender Antimalware Platform. Affected is an unknown function. The manipulation with an unknown input leads to a insufficient granularity of access control vulnerability. CWE is classifying the issue as CWE-1220. The product implements access controls via a policy or other feature with the intention to disable or restrict accesses (reads and/or writes) to assets in a system from untrusted agents. However, implemented access controls lack required granularity, which renders the control policy too broad because it allows accesses from unauthorized agents to the security-sensitive assets. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was released 04/14/2026 as confirmed security update guide (Website). The advisory is available at msrc.microsoft.com. This vulnerability is traded as CVE-2026-33825. The exploitability is told to be easy. Local access is required to approach this attack. Technical details are unknown but an exploit is available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 06/29/2026).

It is declared as attacked. The vulnerability scanner Nessus provides a plugin with the ID 306740 (Security Updates for Windows Defender (April 2026)), which helps to determine the existence of the flaw in a target environment. This issue was added on 04/22/2026 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 05/06/2026:

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Upgrading to version 4.18.26030.3011 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Zero-Day.cz (1092) and Tenable (306740). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Anti-Malware Software

Vendor

Microsoft

Name

Defender Antimalware Platform

License

commercial

Website

Vendor: https://www.microsoft.com/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.8
Vendor Vector (Microsoft): 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Insufficient granularity of access control
CWE: CWE-1220 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Attacked

EPSS Score: 🔒
EPSS Percentile: 🔒

KEV Added: 🔒
KEV Due: 🔒
KEV Remediation: 🔒
KEV Ransomware: 🔒
KEV Notice: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 306740
Nessus Name: Security Updates for Windows Defender (April 2026)

Zero-Day.cz: 🔒

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Upgrade: Defender Antimalware Platform 4.18.26030.3011

Timelineinfo

04/14/2026 VulDB entry created
04/14/2026 +0 days Advisory disclosed
04/14/2026 +0 days Countermeasure disclosed
06/29/2026 +76 days VulDB entry last update