CVE-2026-33566 — There is a cypher injection issue in LogonTracer prior to

title: CVE-2026-33566 - LogonTracer Cypher Injection via Malicious Event Log Data
id: scw-2026-04-27-ai-1
status: experimental
level: critical
description: |
  Detects the loading of specially crafted Windows event log files (.evtx) which could trigger a cypher injection vulnerability in LogonTracer (CVE-2026-33566). This rule specifically targets the file type associated with event logs that the vulnerability exploits, aiming to catch the initial stage of database alteration.
author: SCW Feed Engine (AI-generated)
date: 2026-04-27
references:
  - https://shimiscyberworld.com/posts/nvd-CVE-2026-33566/
tags:
  - attack.initial_access
  - attack.t1190
logsource:
    category: file_event
detection:
  selection:
      TargetFilename|endswith:
          - '.evtx'
      condition: selection
falsepositives:
  - Legitimate administrative activity

Source: Shimi's Cyber World · License & reuse