CVE-2025-25301
📋 TL;DR
CVE-2025-25301 is a server-side request forgery (SSRF) vulnerability in Rembg's API endpoint that allows attackers to fetch and process images from internal network locations. This can lead to information disclosure of internal resources. Users running Rembg 2.0.57 or earlier with the API endpoint exposed are affected.
💻 Affected Systems
- Rembg
📦 What is this software?
Rembg by Danielgatis
⚠️ Risk & Real-World Impact
Worst Case
Complete internal network reconnaissance leading to credential theft, lateral movement, and data exfiltration from internal services.
Likely Case
Information disclosure of internal images and metadata, potentially revealing internal network structure and sensitive data.
If Mitigated
Limited exposure with proper network segmentation and input validation in place.
🎯 Exploit Status
The vulnerability is straightforward to exploit by crafting malicious URL parameters. Public proof-of-concept exists in the GitHub advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.58
Vendor Advisory: https://securitylab.github.com/advisories/GHSL-2024-161_GHSL-2024-162_rembg/
Restart Required: Yes
Instructions:
1. Update Rembg to version 2.0.58 or later using pip: pip install --upgrade rembg==2.0.58
2. Restart any services using Rembg
3. Verify the fix by checking the version
🔧 Temporary Workarounds
Disable URL parameter functionality
allModify the API endpoint to reject URL parameters and only accept direct file uploads
Modify the /api/remove endpoint code to remove URL parameter handling
Network segmentation
allRestrict Rembg server's outbound network access to prevent internal network scanning
Configure firewall rules to block outbound connections from Rembg server to internal networks
🧯 If You Can't Patch
- Implement strict input validation to reject URLs pointing to internal IP ranges (RFC1918, localhost, etc.)
- Deploy network-level controls to restrict the Rembg server's outbound connectivity
🔍 How to Verify
Check if Vulnerable:
Check if Rembg version is 2.0.57 or earlier and the /api/remove endpoint accepts URL parametersCheck Version:
python -c "import rembg; print(rembg.__version__)"Verify Fix Applied:
Test that the /api/remove endpoint no longer processes URLs pointing to internal resources📡 Detection & Monitoring
Log Indicators:
- Unusual URL patterns in API requests
- Requests to internal IP addresses from Rembg server
Network Indicators:
- Outbound connections from Rembg server to internal IP ranges
- Unusual traffic patterns from API endpoint
SIEM Query:
source="rembg" AND (url="*://10.*" OR url="*://192.168.*" OR url="*://172.16.*" OR url="*://127.*" OR url="*://localhost*")