CVE-2021-29219
📋 TL;DR
A local buffer overflow vulnerability in HPE FlexNetwork 5130 EL Switch Series allows attackers with local access to potentially execute arbitrary code or cause denial of service. This affects network administrators and organizations using these switches in vulnerable configurations. The vulnerability stems from improper bounds checking when processing input.
💻 Affected Systems
- HPE FlexNetwork 5130 EL Switch Series
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the switch allowing attacker to execute arbitrary code, modify configurations, intercept network traffic, or cause permanent device failure.
Likely Case
Local privilege escalation or denial of service affecting switch availability and network operations.
If Mitigated
Limited impact due to network segmentation and restricted administrative access, potentially resulting only in service disruption.
🎯 Exploit Status
Exploitation requires local access and knowledge of the buffer overflow. No public exploits have been disclosed as of the advisory date.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 5130_EL_7.10.R3507P02
Vendor Advisory: https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbnw04234en_us
Restart Required: Yes
Instructions:
1. Download firmware version 5130_EL_7.10.R3507P02 from HPE support portal. 2. Backup current configuration. 3. Upload new firmware via TFTP/SCP. 4. Reboot switch to apply update. 5. Verify firmware version after reboot.
🔧 Temporary Workarounds
Restrict Management Access
allLimit access to switch management interfaces to trusted networks and IP addresses only
# Configure ACL to restrict management access
acl number 2000
rule 5 permit source 10.0.0.0 0.255.255.255
user-interface vty 0 4
acl 2000 inbound
Disable Unused Services
allTurn off unnecessary management services to reduce attack surface
# Disable unused services
undo telnet server enable
undo ftp server enable
undo http server enable
🧯 If You Can't Patch
- Implement strict network segmentation to isolate switch management interfaces
- Enable logging and monitoring for unauthorized access attempts to switch management
🔍 How to Verify
Check if Vulnerable:
Check current firmware version via CLI: display version. If version is earlier than 5130_EL_7.10.R3507P02, the system is vulnerable.Check Version:
display versionVerify Fix Applied:
After patching, run: display version and confirm version shows 5130_EL_7.10.R3507P02 or later.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts
- Unexpected configuration changes
- System crash or reboot events
- Buffer overflow error messages in system logs
Network Indicators:
- Unusual traffic patterns from switch management interfaces
- Unexpected connections to switch management ports
- Traffic indicating privilege escalation attempts
SIEM Query:
source="switch*" AND (event_type="authentication_failure" OR event_type="system_crash" OR message="*buffer*overflow*")