CVE-2022-23011
📋 TL;DR
This vulnerability affects F5 BIG-IP platforms running specific versions, causing virtual servers to become unresponsive when processing TCP traffic due to a flaw in the SYN Cookie Protection feature. It impacts BIG-IP hardware platforms running versions 15.1.x before 15.1.4 and 14.1.x before 14.1.3, potentially leading to denial of service conditions.
💻 Affected Systems
- F5 BIG-IP hardware platforms
📦 What is this software?
Big Ip Application Acceleration Manager by F5
View all CVEs affecting Big Ip Application Acceleration Manager →
Big Ip Application Acceleration Manager by F5
View all CVEs affecting Big Ip Application Acceleration Manager →
Big Ip Application Acceleration Manager by F5
View all CVEs affecting Big Ip Application Acceleration Manager →
Big Ip Application Acceleration Manager by F5
View all CVEs affecting Big Ip Application Acceleration Manager →
Big Ip Application Acceleration Manager by F5
View all CVEs affecting Big Ip Application Acceleration Manager →
Big Ip Application Acceleration Manager by F5
View all CVEs affecting Big Ip Application Acceleration Manager →
Big Ip Application Security Manager by F5
View all CVEs affecting Big Ip Application Security Manager →
Big Ip Application Security Manager by F5
View all CVEs affecting Big Ip Application Security Manager →
Big Ip Application Security Manager by F5
View all CVEs affecting Big Ip Application Security Manager →
Big Ip Application Security Manager by F5
View all CVEs affecting Big Ip Application Security Manager →
Big Ip Application Security Manager by F5
View all CVEs affecting Big Ip Application Security Manager →
⚠️ Risk & Real-World Impact
Worst Case
Complete denial of service for affected virtual servers, making services unavailable to legitimate users.
Likely Case
Intermittent service disruptions and performance degradation for TCP-based services.
If Mitigated
Minimal impact with proper monitoring and quick failover to unaffected systems.
🎯 Exploit Status
Exploitation requires sending TCP traffic to vulnerable virtual servers, which is trivial for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 15.1.4 or later, 14.1.3 or later
Vendor Advisory: https://support.f5.com/csp/article/K68755210
Restart Required: Yes
Instructions:
1. Download the appropriate patch from F5 Downloads. 2. Backup current configuration. 3. Apply the patch following F5's upgrade procedures. 4. Restart the system as required. 5. Verify functionality post-upgrade.
🔧 Temporary Workarounds
Disable SYN Cookie Protection
allTemporarily disable the affected SYN Cookie Protection feature to prevent the vulnerability from being triggered.
tmsh modify sys db tcp.syncookies value disable
Implement Rate Limiting
allConfigure rate limiting on TCP connections to reduce the likelihood of triggering the vulnerability.
tmsh modify ltm virtual <virtual_server_name> rate-limit <limit_value>
🧯 If You Can't Patch
- Implement network segmentation to restrict access to vulnerable virtual servers
- Deploy additional monitoring and alerting for service availability
🔍 How to Verify
Check if Vulnerable:
Check BIG-IP version with 'tmsh show sys version' and verify if it's in the affected range (15.1.x before 15.1.4 or 14.1.x before 14.1.3).Check Version:
tmsh show sys versionVerify Fix Applied:
After patching, verify version is 15.1.4+ or 14.1.3+ and monitor virtual server responsiveness to TCP traffic.📡 Detection & Monitoring
Log Indicators:
- Virtual server state changes to 'down'
- Increased TCP connection errors
- SYN flood protection alerts
Network Indicators:
- Unresponsive virtual servers on TCP ports
- Increased TCP retransmissions
- Connection timeouts
SIEM Query:
source="bigip.log" AND ("virtual server down" OR "TCP connection error" OR "SYN cookie")