CVE-2020-5601
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary commands through the Chrome Extension for e-Tax Reception System Ver1.0.0.0. Attackers can potentially take control of affected systems by exploiting unspecified vectors in the extension. Users of the e-Tax Reception System with the vulnerable Chrome extension installed are affected.
💻 Affected Systems
- Chrome Extension for e-Tax Reception System
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with remote code execution, allowing attackers to install malware, steal sensitive tax data, or pivot to other systems.
Likely Case
Attackers execute commands to steal authentication credentials, tax documents, or install keyloggers to capture sensitive financial information.
If Mitigated
Limited impact if extension is disabled or removed, though system may remain vulnerable until patched.
🎯 Exploit Status
The vulnerability allows remote command execution via unspecified vectors, suggesting relatively straightforward exploitation once vectors are identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Ver1.0.0.1 or later
Vendor Advisory: https://www.e-tax.nta.go.jp/topics/topics_200618.htm
Restart Required: No
Instructions:
1. Open Chrome browser. 2. Go to chrome://extensions/. 3. Find 'e-Tax Reception System' extension. 4. Remove the extension. 5. Visit Chrome Web Store or vendor site to install updated version 1.0.0.1 or later.
🔧 Temporary Workarounds
Disable Chrome Extension
allTemporarily disable the vulnerable extension to prevent exploitation
chrome://extensions/ -> Toggle off 'e-Tax Reception System' extension
Remove Extension
allCompletely remove the vulnerable extension from Chrome
chrome://extensions/ -> Click 'Remove' on 'e-Tax Reception System' extension
🧯 If You Can't Patch
- Disable or remove the Chrome extension immediately
- Use alternative methods to access e-Tax system until extension is updated
🔍 How to Verify
Check if Vulnerable:
Check Chrome extensions at chrome://extensions/ and verify if 'e-Tax Reception System' extension version is 1.0.0.0Check Version:
chrome://extensions/ -> Find 'e-Tax Reception System' -> Check version numberVerify Fix Applied:
After update, verify extension version shows 1.0.0.1 or later in chrome://extensions/📡 Detection & Monitoring
Log Indicators:
- Unusual Chrome extension activity
- Suspicious command execution from browser context
- Unexpected network connections from Chrome
Network Indicators:
- Unusual outbound connections from Chrome browser
- Traffic to unexpected domains
SIEM Query:
source="chrome" AND (extension_name="e-Tax Reception System" OR process="chrome.exe") AND (event="command_execution" OR event="unusual_network")