Vulnerability in F5 Nginx_gateway_fabric
CVE-2026-1642
A vulnerability exists in NGINX OSS and NGINX Plus when configured to proxy to upstream Transport Layer Security (TLS) servers. An attacker with a man-in-the-middle (MITM) position on the upstream server side—along with conditions beyond t…
EPSS: 0.003 (26.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.
Affected products
- F5 Nginx_gateway_fabric
- F5 Nginx_ingress_controller
- F5 Nginx_instance_manager
- F5 Nginx Open Source — versions 1.3.0
- F5 Nginx_open_source
- F5 Nginx Plus — versions R36, R35, R34
- F5 Nginx_plus — versions r32, r33, r34
Weakness classification (CWE)
References
- f5sirt@f5.com (vendor-advisory, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-1642?
- CVE-2026-1642 is a medium-severity vulnerability in F5 Nginx_gateway_fabric, classified under CWE-349. CVSS score: 5.9/10. Published 2026-02-04.
- How severe is CVE-2026-1642?
- Medium severity. CVSS v3 base score is 5.9 out of 10.