CVE-2024-39548
📋 TL;DR
An unauthenticated attacker can send network traffic to Juniper Junos OS Evolved devices to cause uncontrolled memory consumption in the aftmand process, leading to a denial of service. The affected processes do not recover automatically and require manual restart. This vulnerability affects multiple Junos OS Evolved versions across both IPv4 and IPv6.
💻 Affected Systems
- Juniper Networks Junos OS Evolved
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete denial of service on affected network devices requiring manual intervention to restore functionality, potentially disrupting critical network operations.
Likely Case
Degraded performance or service interruption on vulnerable devices until processes are manually restarted.
If Mitigated
Limited impact with proper network segmentation and monitoring allowing quick detection and response.
🎯 Exploit Status
Unauthenticated network-based attack with no authentication required. Specific exploit details not publicly available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 21.2R3-S8-EVO, 21.3R3-S5-EVO, 21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R2-S2-EVO, 22.4R3-EVO, 23.2R1-S1-EVO, 23.2R2-EVO and later versions
Vendor Advisory: https://supportportal.juniper.net/JSA83010
Restart Required: Yes
Instructions:
1. Check current version with 'show version'. 2. Download appropriate patched version from Juniper support portal. 3. Follow Junos OS Evolved upgrade procedures. 4. Reboot device after upgrade.
🔧 Temporary Workarounds
Memory Monitoring
allMonitor memory usage of evo-aftmand process to detect exploitation attempts
show system memory node <fpc slot> | grep evo-aftmand
🧯 If You Can't Patch
- Implement network segmentation to limit access to affected devices
- Monitor for abnormal memory consumption and have procedures for manual process restart
🔍 How to Verify
Check if Vulnerable:
Check current version with 'show version' and compare against affected versions listCheck Version:
show versionVerify Fix Applied:
Verify version is patched with 'show version' and monitor evo-aftmand process memory usage📡 Detection & Monitoring
Log Indicators:
- Unusual memory consumption alerts
- Process crash logs for aftmand
Network Indicators:
- Unusual traffic patterns to affected devices
- Increased memory usage without corresponding legitimate traffic
SIEM Query:
Process:name='evo-aftmand' AND MemoryUsage>threshold