On BIG-IP LTM/CGNAT version 16.0.0-16.0.0.1, 15.1.0-15.1.0.5, 14.1.0-14.1.3, and…
Priority LOW 35Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
On BIG-IP LTM/CGNAT version 16.0.0-16.0.0.1, 15.1.0-15.1.0.5, 14.1.0-14.1.3, and 13.1.0-13.1.3.5, when processing NAT66 traffic with Port Block Allocation (PBA) mode and SP-DAG enabled, and dag-ipv6-prefix-len configured with a value less than the default of 128, an undisclosed traffic pattern may cause the Traffic Management Microkernel (TMM) to restart.
Why it matters now
EPSS 0.01252 69th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | BIG-IP LTM/CGNAT | 16.0.0-16.0.0.1, 15.1.0-15.1.0.5, 14.1.0-14.1.3, 13.1.0-13.1.3.5 | — | No fix listed | CNA |
- BIG-IP LTM/CGNAT Vendor— Affected 16.0.0-16.0.0.1, 15.1.0-15.1.0.5, 14.1.0-14.1.3, 13.1.0-13.1.3.5 Fixed in — No fix listed CNA
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:f5:big-ip_carrier-grade_nat:*:*:*:*:*:*:*:* | 13.1.0 – 13.1.3; 14.1.0 to before 14.1.3.1; 15.1.0 to before 15.1.1; 16.0.0 to before 16.0.1 | Vulnerable | F5 |
| cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:* | 13.1.0 – 13.1.3; 14.1.0 to before 14.1.3.1; 15.1.0 to before 15.1.1; 16.0.0 to before 16.0.1 | Vulnerable | F5 |
- cpe:2.3:a:f5:big-ip_carrier-grade_nat:*:*:*:*:*:*:*:* Versions 13.1.0 – 13.1.3; 14.1.0 to before 14.1.3.1; 15.1.0 to before 15.1.1; 16.0.0 to before 16.0.1 Vulnerable ·F5
- cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:* Versions 13.1.0 – 13.1.3; 14.1.0 to before 14.1.3.1; 15.1.0 to before 15.1.1; 16.0.0 to before 16.0.1 Vulnerable ·F5
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-27720
- 2026-10-03 Alias added: GHSA-hp39-4vrr-9cjg
References
More F5 Big-ip Carrier-grade Nat vulnerabilities
- TI-2023-25230 BIG-IP Configuration utility unauthenticated remote code execution vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2023-25231 BIG-IP Configuration utility authenticated SQL injection vulnerability KEVCVSS 3.1HIGH 8.8
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2025-14341 BIG-IP iControl REST and tmsh vulnerability CVSS 4.0HIGH 8.7
- TI-2025-22807 Appliance mode BIG-IP iControl REST and tmsh vulnerability CVSS 4.0HIGH 8.5
- TI-2024-30801 BIG-IP monitors vulnerability CVSS 4.0HIGH 8.6
Sources
- CVE-2020-27720 · CVE Program
- CVE-2020-27720 · NVD
- FIRST EPSS
- GHSA-hp39-4vrr-9cjg · GitHub Advisory Database · CC BY 4.0
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