CVE-2025-8872
📋 TL;DR
This vulnerability allows attackers to send specially crafted OSPFv3 packets to Arista EOS devices, causing high CPU utilization that can restart the OSPFv3 process and disrupt routing. It affects Arista EOS platforms with OSPFv3 configured. The issue was discovered internally by Arista with no known malicious exploitation.
💻 Affected Systems
- Arista EOS
⚠️ 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
Sustained attacks could cause repeated OSPFv3 process restarts leading to extended routing disruptions, network instability, and potential denial of service across the network.
Likely Case
Temporary OSPFv3 process restarts causing brief routing flaps and convergence delays, potentially affecting network performance until the attack stops.
If Mitigated
With proper network segmentation and access controls, impact is limited to isolated network segments with minimal disruption.
🎯 Exploit Status
Exploitation requires network access to OSPFv3-enabled interfaces and ability to send crafted packets. No authentication required once network access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Arista security advisory for fixed versions
Vendor Advisory: https://www.arista.com/en/support/advisories-notices/security-advisory/23115-security-advisory-0128
Restart Required: Yes
Instructions:
1. Review Arista security advisory for affected versions. 2. Upgrade to fixed EOS version. 3. Schedule maintenance window for router restart. 4. Apply patch and restart affected devices.
🔧 Temporary Workarounds
Disable OSPFv3
allTemporarily disable OSPFv3 if not required for network operations
configure terminal
no router ospfv3
Implement OSPFv3 Authentication
allConfigure OSPFv3 authentication to prevent unauthorized adjacency
configure terminal
router ospfv3
area 0 authentication ipsec spi 256 sha1 <key>
🧯 If You Can't Patch
- Implement strict network segmentation to isolate OSPFv3 traffic
- Deploy network monitoring and intrusion detection for OSPFv3 anomalies
🔍 How to Verify
Check if Vulnerable:
Check if OSPFv3 is configured: 'show running-config | include router ospfv3' and compare EOS version against Arista advisoryCheck Version:
show version | include Software image versionVerify Fix Applied:
Verify EOS version after upgrade: 'show version' and confirm OSPFv3 is functioning: 'show ipv6 ospfv3 neighbor'📡 Detection & Monitoring
Log Indicators:
- OSPFv3 process restart messages
- High CPU utilization alerts for OSPFv3 process
- Routing flap notifications
Network Indicators:
- Unusual OSPFv3 packet patterns
- OSPFv3 adjacency flapping
- Increased OSPFv3 traffic to single device
SIEM Query:
source="arista-router" ("OSPFv3" AND ("restart" OR "high cpu" OR "flap"))