CVE-2026-0791
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on ALGO 8180 IP Audio Alerter devices without authentication by sending specially crafted SIP INVITE requests with malicious Replaces headers. The buffer overflow occurs when the device copies user-supplied data to a fixed-length stack buffer without proper length validation. All organizations using affected ALGO 8180 devices are at risk.
💻 Affected Systems
- ALGO 8180 IP Audio Alerter
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to install persistent malware, pivot to internal networks, disable critical alerting systems, or use devices as botnet nodes.
Likely Case
Device takeover leading to service disruption, unauthorized audio playback, credential theft, or lateral movement within the network.
If Mitigated
Limited impact if devices are properly segmented and monitored, though service disruption remains possible.
🎯 Exploit Status
The vulnerability is unauthenticated and requires only network access to SIP port (typically 5060). Exploit development is straightforward given the public vulnerability details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific patched version
Vendor Advisory: https://www.zerodayinitiative.com/advisories/ZDI-26-013/
Restart Required: Yes
Instructions:
1. Check ALGO vendor website for security advisory
2. Download latest firmware update
3. Backup device configuration
4. Apply firmware update via web interface or console
5. Reboot device
6. Verify update applied successfully
🔧 Temporary Workarounds
Network Segmentation
allIsolate ALGO 8180 devices from untrusted networks and restrict SIP traffic
Firewall Rules
allBlock external access to SIP port (5060) and restrict internal access to authorized systems only
🧯 If You Can't Patch
- Immediately isolate affected devices in a dedicated VLAN with strict firewall rules
- Implement network monitoring for anomalous SIP traffic patterns and buffer overflow attempts
🔍 How to Verify
Check if Vulnerable:
Check device firmware version against vendor advisory. If unable to patch, test with controlled exploit attempt in isolated environment.Check Version:
Check via device web interface under System > Firmware or via console command (vendor-specific)Verify Fix Applied:
Verify firmware version matches patched version from vendor advisory and test that malformed SIP INVITE requests no longer cause crashes.📡 Detection & Monitoring
Log Indicators:
- Device crash/restart logs
- Unusual SIP traffic patterns
- Multiple failed SIP requests from single source
Network Indicators:
- SIP INVITE packets with unusually long Replaces headers
- Traffic to device SIP port from unexpected sources
- Buffer overflow patterns in SIP traffic
SIEM Query:
source_port:5060 AND (header_length > 1000 OR contains("Replaces:"))