CVE-2022-32073
📋 TL;DR
CVE-2022-32073 is an integer overflow vulnerability in WolfSSH's SFTP server component that can lead to buffer overflow and potential remote code execution. This affects systems running WolfSSH v1.4.7 with SFTP enabled. Attackers could exploit this to crash the service or execute arbitrary code.
💻 Affected Systems
- WolfSSH
📦 What is this software?
Wolfssh by Wolfssh
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the WolfSSH process, potentially leading to full system compromise.
Likely Case
Service crash (denial of service) or limited memory corruption leading to unstable behavior.
If Mitigated
Minimal impact if SFTP is disabled or proper input validation is implemented.
🎯 Exploit Status
Exploitation requires sending specially crafted SFTP packets to trigger the integer overflow.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v1.4.8 and later
Vendor Advisory: https://github.com/wolfSSL/wolfssh/pull/360
Restart Required: Yes
Instructions:
1. Download WolfSSH v1.4.8 or later from official repository. 2. Replace vulnerable version. 3. Recompile if using source. 4. Restart all WolfSSH services.
🔧 Temporary Workarounds
Disable SFTP functionality
allDisable SFTP server component if not required
Configure WolfSSH to disable SFTP (check documentation for specific configuration)
Network segmentation
linuxRestrict access to WolfSSH services
iptables -A INPUT -p tcp --dport 22 -s trusted_networks -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -j DROP
🧯 If You Can't Patch
- Implement strict network access controls to limit exposure
- Monitor for abnormal SFTP traffic patterns and connection attempts
🔍 How to Verify
Check if Vulnerable:
Check WolfSSH version: wolfssh-config --version or examine binary/package versionCheck Version:
wolfssh-config --version || strings /path/to/wolfssh | grep -i versionVerify Fix Applied:
Verify version is v1.4.8 or later and test SFTP functionality📡 Detection & Monitoring
Log Indicators:
- Abnormal SFTP connection terminations
- WolfSSH process crashes
- Memory allocation errors in logs
Network Indicators:
- Unusual SFTP packet sizes
- Multiple rapid SFTP connection attempts
SIEM Query:
source="wolfssh.log" AND ("crash" OR "segfault" OR "overflow")