CVE-2025-7627
📋 TL;DR
This critical vulnerability in YiJiuSmile kkFileViewOfficeEdit allows remote attackers to upload arbitrary files without restrictions via the /fileUpload endpoint. Affected systems are those running versions up to commit 5fbc57c48e8fe6c1b91e0e7995e2d59615f37abd, which uses a rolling release model without specific version details.
💻 Affected Systems
- YiJiuSmile kkFileViewOfficeEdit
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through remote code execution via malicious file upload leading to web shell deployment, data theft, or ransomware deployment.
Likely Case
Unauthorized file upload leading to web shell installation, data exfiltration, or service disruption through file system manipulation.
If Mitigated
Limited impact with proper file upload validation, but potential for denial of service through resource exhaustion.
🎯 Exploit Status
Exploit details are publicly disclosed in GitHub issue #14, making this easily exploitable by attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown - rolling release model
Vendor Advisory: https://github.com/YiJiuSmile/kkFileViewOfficeEdit/issues/14
Restart Required: No
Instructions:
Check GitHub repository for updated commits after 5fbc57c48e8fe6c1b91e0e7995e2d59615f37abd and update to latest version. Since this is rolling release, pull latest code from repository.
🔧 Temporary Workarounds
Disable file upload endpoint
allTemporarily disable or block access to the /fileUpload endpoint
# Web server configuration to block /fileUpload
# For nginx: location /fileUpload { deny all; }
# For Apache: <Location /fileUpload> Require all denied </Location>
Implement file upload validation
allAdd server-side file type validation and size restrictions
# Implement file extension whitelisting
# Implement MIME type validation
# Set maximum file size limits
🧯 If You Can't Patch
- Implement WAF rules to block malicious file upload patterns
- Isolate the vulnerable system in a restricted network segment
🔍 How to Verify
Check if Vulnerable:
Check if /fileUpload endpoint accepts arbitrary file types without validation. Test by uploading a file with .php, .jsp, or other executable extensions.Check Version:
git log --oneline -1 # Check latest commit hash against vulnerable commitVerify Fix Applied:
Verify that file upload endpoint now validates file types, extensions, and content. Test that malicious file uploads are rejected.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to /fileUpload endpoint
- Uploads of executable file types (.php, .jsp, .exe)
- Large number of upload requests from single IP
Network Indicators:
- POST requests to /fileUpload with suspicious file names
- Traffic patterns showing file uploads followed by execution attempts
SIEM Query:
source="web_logs" AND uri="/fileUpload" AND (file_extension="php" OR file_extension="jsp" OR file_extension="exe")