CVE-2025-43971
📋 TL;DR
This vulnerability in GoBGP allows attackers to trigger a denial of service by sending specially crafted BGP packets with a zero value for softwareVersionLen, causing the application to panic and crash. All systems running vulnerable versions of GoBGP are affected, particularly network infrastructure using GoBGP for BGP routing.
💻 Affected Systems
- GoBGP
📦 What is this software?
Gobgp by Osrg
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption of BGP routing, causing network outages and potential cascading failures in dependent systems.
Likely Case
Denial of service affecting BGP routing functionality, requiring service restart and potentially causing temporary network instability.
If Mitigated
Minimal impact if proper network segmentation and input validation are in place to filter malicious BGP packets.
🎯 Exploit Status
Exploitation requires sending a malformed BGP packet, which is straightforward for attackers with BGP peer access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.35.0
Vendor Advisory: https://github.com/osrg/gobgp/commit/08a001e06d90e8bcc190084c66992f46f62c0986
Restart Required: Yes
Instructions:
1. Stop GoBGP service. 2. Update to version 3.35.0 or later using package manager or source compilation. 3. Restart GoBGP service.
🔧 Temporary Workarounds
BGP Packet Filtering
allUse network firewalls or BGP session filters to block malformed BGP packets from untrusted sources.
Restrict BGP Peer Access
allLimit BGP connections to trusted peers only using access control lists.
🧯 If You Can't Patch
- Implement strict BGP peer authentication and limit connections to known trusted peers only.
- Deploy network monitoring to detect and alert on GoBGP service crashes or restarts.
🔍 How to Verify
Check if Vulnerable:
Check GoBGP version: if version is below 3.35.0, the system is vulnerable.Check Version:
gobgpd --versionVerify Fix Applied:
Confirm GoBGP version is 3.35.0 or higher and monitor for crashes after applying patch.📡 Detection & Monitoring
Log Indicators:
- GoBGP panic logs
- Unexpected service termination
- BGP session resets
Network Indicators:
- Unusual BGP packet patterns
- BGP session flaps from specific peers
SIEM Query:
source="gobgp.log" AND (panic OR crash OR "unexpected EOF")