CVE-2026-1691
📋 TL;DR
This CVE describes a remote deserialization vulnerability in bolo-solo's SnakeYAML component that allows attackers to execute arbitrary code by manipulating markdown import functionality. The vulnerability affects bolo-solo versions up to 2.6.4. Attackers can exploit this remotely without authentication to potentially take control of affected systems.
💻 Affected Systems
- bolo-solo
📦 What is this software?
Bolo Solo by Adlered
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, and lateral movement within the network.
Likely Case
Remote code execution allowing attackers to deploy malware, create backdoors, or disrupt service availability.
If Mitigated
Limited impact if proper network segmentation and input validation are in place, though deserialization attacks remain dangerous.
🎯 Exploit Status
Exploit details have been publicly disclosed on GitHub, making weaponization likely. The deserialization vulnerability pattern is well-known and easily exploitable.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 2.6.5 or later
Vendor Advisory: https://github.com/bolo-blog/bolo-solo/issues/325
Restart Required: Yes
Instructions:
1. Backup your data and configuration. 2. Download bolo-solo version 2.6.5 or later from the official repository. 3. Replace the existing installation with the patched version. 4. Restart the bolo-solo service.
🔧 Temporary Workarounds
Disable markdown import functionality
allTemporarily disable the vulnerable importMarkdownsSync function by modifying configuration or removing access to the backup/restore feature.
# Edit configuration to disable backup/import features
# Remove or comment out backup-related endpoints in web.xml or similar configuration
Network isolation
linuxRestrict network access to bolo-solo instances using firewall rules to limit exposure.
# Example iptables rule: iptables -A INPUT -p tcp --dport [bolo-port] -s [trusted-ips] -j ACCEPT
# Then: iptables -A INPUT -p tcp --dport [bolo-port] -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable instances from untrusted networks
- Deploy web application firewall (WAF) rules to block deserialization payloads and suspicious requests
🔍 How to Verify
Check if Vulnerable:
Check the bolo-solo version number in the application interface or configuration files. Versions 2.6.4 and below are vulnerable.Check Version:
Check the version in the web interface or examine the application's version file if available.Verify Fix Applied:
Verify the installed version is 2.6.5 or later. Test the markdown import functionality with safe test data to ensure it works without errors.📡 Detection & Monitoring
Log Indicators:
- Unusual markdown import requests
- Java deserialization errors in logs
- Unexpected process execution from bolo-solo
- Large or malformed YAML/JSON payloads in requests
Network Indicators:
- HTTP POST requests to backup/import endpoints with serialized data
- Unusual outbound connections from bolo-solo instances
SIEM Query:
source="bolo-solo" AND (event="importMarkdownsSync" OR message="*deserialization*" OR status=500)