# CVE-2026-33825: Microsoft Defender Insufficient Granularity of Access Control

> An authorized local attacker can elevate privileges due to insufficient access control granularity in Microsoft Defender.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C`)
- **Exploited in the wild:** Yes, since 22 Apr 2026 (CISA KEV), used in ransomware
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Apr 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-8vp7-4rmv-4868

## What is CVE-2026-33825?

CVE-2026-33825 is a high-severity vulnerability in Microsoft Defender Antimalware Platform, published on 14 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.

Weakness: CWE-1220 (Insufficient Granularity of Access Control)

## Which versions are affected by CVE-2026-33825?

It affects 1 product.


Products: Microsoft Defender Antimalware Platform.

## How do I fix CVE-2026-33825?

No fix has been published for CVE-2026-33825 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 6 May 2026.

## Is CVE-2026-33825 being exploited?

Yes. Attackers have exploited CVE-2026-33825 in the wild since at least 22 Apr 2026, including in ransomware campaigns.

Public exploit code:

- Microsoft Defender XDR KQL detections for RedSun, BlueHammer, UnDefend, and CVE-2026-33825-related Defender abuse behaviors. (github_poc): https://github.com/Letlaka/redsun-bluehammer-undefend-detection-pack
- CVE-2026-33825 (github_poc): https://github.com/0xredash/CVE-2026-33825
- RedSun PoC for self use (github_poc): https://github.com/Joe1sn/CVE-2026-33825
- Threat hunting query for bluehammer CVE windows CVE-2026-33825 (github_poc): https://github.com/Bilal3755/Detecting_blue_hammer_vuln
- https://github.com/kaleth4/CVE-2026-33825 (github_poc): https://github.com/kaleth4/CVE-2026-33825
- Defensive Metasploit post module for CVE-2026-33825 (BlueHammer): Defender version/posture detection + compromise-hunt. Detection only. (github_poc): https://github.com/anasabugaddara-ux/defender-bluehammer-audit

## Other vulnerabilities in Microsoft Defender Antimalware Platform

- [CVE-2026-45498](https://insights.sbomify.com/CVE-2026-45498/): Microsoft Defender Denial of Service (medium 4.0, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33825 and fix it if it is affected.

What it is: CVE-2026-33825 is a high-severity vulnerability in Microsoft Defender Antimalware Platform, published on 14 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2026-33825 in the wild since at least 22 Apr 2026, including in ransomware campaigns.

Affected product: Microsoft Defender Antimalware Platform. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-33825/ (Markdown: https://insights.sbomify.com/CVE-2026-33825/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33825
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33825
- OSV: https://osv.dev/vulnerability/CVE-2026-33825

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33825/
Summaries are generated and may contain mistakes; the official description above is the record.