CVE-2025-6188
📋 TL;DR
Arista EOS devices accept malicious UDP packets on port 3503 (LspPing Echo Reply), potentially allowing attackers to trigger unexpected behaviors in UDP services lacking authentication. This affects Arista EOS platforms running vulnerable versions. The vulnerability enables potential denial-of-service or service disruption.
💻 Affected Systems
- Arista EOS (Extensible Operating System)
⚠️ 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 network disruption through denial-of-service attacks on critical UDP services, potentially affecting routing protocols or network management functions.
Likely Case
Service degradation or instability for UDP-based services, potentially causing intermittent connectivity issues or performance problems.
If Mitigated
Minimal impact with proper network segmentation, firewall rules, and updated systems.
🎯 Exploit Status
Exploitation requires sending specially crafted UDP packets to port 3503. No authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Arista advisory for specific fixed versions
Vendor Advisory: https://www.arista.com/en/support/advisories-notices/security-advisory/22021-security-advisory-0121
Restart Required: Yes
Instructions:
1. Review Arista advisory for exact fixed versions. 2. Schedule maintenance window. 3. Backup configuration. 4. Upgrade to patched EOS version. 5. Verify functionality post-upgrade.
🔧 Temporary Workarounds
Block UDP port 3503
allUse access control lists or firewall rules to block UDP traffic on port 3503 from untrusted sources.
Example ACL: 'ip access-list standard BLOCK-UDP-3503', 'deny udp any any eq 3503', 'permit ip any any'
Network segmentation
allIsolate affected devices to limit potential attack surface and contain any exploitation.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable devices
- Deploy intrusion detection/prevention systems to monitor for malicious UDP packets on port 3503
🔍 How to Verify
Check if Vulnerable:
Check EOS version against vulnerable versions listed in Arista advisory. Verify if UDP port 3503 is open and accessible.Check Version:
show version | include Software image versionVerify Fix Applied:
Confirm EOS version is updated to patched version from advisory. Test that UDP port 3503 properly handles or rejects malicious packets.📡 Detection & Monitoring
Log Indicators:
- Unexpected UDP traffic on port 3503
- LspPing protocol anomalies
- Service disruptions or restarts
Network Indicators:
- Unusual UDP packet patterns to port 3503
- Malformed UDP packets with source port 3503
SIEM Query:
source_port:3503 AND protocol:UDP AND (packet_size:anomalous OR packet_pattern:malicious)