CVE-2026-40701

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssl_module module when the ssl_verify_client directive is set to "on" or "optional," and the ssl_ocsp directive is set to "on" or the leaf parameters are configured with a resolver. With this configuration, an unauthenticated attacker can send requests along with conditions beyond its control that may cause a heap-use-after-free error in the NGINX worker process. This vulnerability may result in limited modification of data or the NGINX worker process restarting.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected products

Linuxmint, Nginx Open Source, Nginx Plus, Nginx, Red Os, Ubuntu

f5 Dos

≤ 4.7.0, 4.8.0

f5 Nginx Gateway Fabric

≤ 1.6.2, 2.6.0

f5 Nginx Ingress Controller

≤ 3.7.2, 4.0.1, 5.4.2

f5 Nginx Instance Manager

≤ 2.22.0

f5 Nginx Open Source

≤ 1.30.0

f5 Nginx Plus

≤ R36

CVSS 4.0

6.3 MEDIUM

CVSS 3.1

4.8 MEDIUM

EPSS

0.7% (50th percentile)

Weakness

CWE-416

NVD status

Analyzed

Published

2026-05-13