---
id: CVE-2026-40701
title: "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 wi…"
summary: "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 wi…"
severity: medium
cvss: 4.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L'
cwe:
  - CWE-416
published: '2026-05-13'
updated: '2026-06-23'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-40701'
references:
  - url: 'https://my.f5.com/manage/s/article/K000161021'
    label: f5sirt@f5.com
tags:
  - nvd
  - exploit-available
epss: 0.0069
epssPercentile: 0.514
ingestedAt: '2026-06-29T13:24:34.845Z'
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/edgecases-PurpleHax/cve-images'
  checkedAt: '2026-09-24T07:53:03.195Z'
exploitAvailable: true
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.