CVE-2025-34458
📋 TL;DR
CVE-2025-34458 is a reachable assertion vulnerability in Dire Wolf's APRS MIC-E decoder that causes immediate process termination when processing specially crafted AX.25 frames with empty or truncated comment fields. This allows remote, unauthenticated attackers to cause denial of service by sending malformed APRS traffic. All Dire Wolf users running vulnerable versions are affected.
💻 Affected Systems
- wb2osz/direwolf (Dire Wolf)
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption of Dire Wolf APRS processing, potentially affecting critical communications infrastructure relying on APRS for position reporting or messaging.
Likely Case
Intermittent service outages as attackers send malformed packets to crash Dire Wolf instances, requiring manual restart of affected services.
If Mitigated
Minimal impact with proper network segmentation and monitoring to detect and block malicious APRS traffic before it reaches vulnerable systems.
🎯 Exploit Status
The vulnerability is trivially exploitable by sending specially crafted AX.25 frames with empty comment fields in MIC-E messages. Public proof-of-concept details are available in security advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit 3658a87 and later, or any version after 1.8
Vendor Advisory: https://github.com/wb2osz/direwolf/commit/3658a87
Restart Required: Yes
Instructions:
1. Update Dire Wolf to the latest version from the official GitHub repository
2. Alternatively, apply commit 3658a87 to your existing installation
3. Recompile Dire Wolf from source if using custom builds
4. Restart all Dire Wolf services and processes
🔧 Temporary Workarounds
Network Filtering
allBlock or filter malicious APRS traffic at network boundaries using firewalls or intrusion prevention systems
Process Monitoring and Auto-restart
linuxImplement process monitoring with automatic restart capabilities to minimize downtime
# Example using systemd (Linux)
[Unit]
Description=Dire Wolf APRS
After=network.target
[Service]
Type=simple
ExecStart=/usr/local/bin/direwolf
Restart=always
RestartSec=5
[Install]
WantedBy=multi-user.target
🧯 If You Can't Patch
- Implement strict network segmentation to isolate Dire Wolf instances from untrusted networks
- Deploy network monitoring to detect and alert on malformed APRS traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check if Dire Wolf version is 1.8 or earlier and doesn't include commit 3658a87. Run 'direwolf -v' to check version.Check Version:
direwolf -v 2>&1 | grep -i versionVerify Fix Applied:
Verify the installed version is after 1.8 or includes commit 3658a87. Check git log for commit hash if built from source.📡 Detection & Monitoring
Log Indicators:
- Dire Wolf process crashes with assertion failure messages
- Error logs containing 'assertion failed' or 'aprs_mic_e' function references
- Sudden service termination without normal shutdown
Network Indicators:
- Unusual APRS traffic patterns with malformed MIC-E messages
- AX.25 frames with empty comment fields
- Traffic from unexpected sources targeting APRS ports
SIEM Query:
process_name="direwolf" AND (event_type="crash" OR log_message CONTAINS "assertion" OR log_message CONTAINS "aprs_mic_e")