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.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000161021

Configurations

No configuration.

History

13 May 2026, 16:27

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-13 16:16

Updated : 2026-05-13 16:27

NVD link : CVE-2026-40701

Mitre link : CVE-2026-40701

CVE.ORG link : CVE-2026-40701

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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