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	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:f5:dos::::::nginx::*
	cpe:2.3:a:f5:dos:4.8.0:::::nginx::
	cpe:2.3:a:f5:nginx_gateway_fabric::::::::
	cpe:2.3:a:f5:nginx_gateway_fabric::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_instance_manager::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_plus::::::::
	cpe:2.3:a:f5:waf::::::nginx::*
	cpe:2.3:a:f5:waf::::::nginx::*
	cpe:2.3:a:f5:waf::::::nginx::*

History

No history.

Information

Published : 2026-05-13 16:16

Updated : 2026-06-23 13:57

NVD link : CVE-2026-40701

Mitre link : CVE-2026-40701

CVE.ORG link : CVE-2026-40701

JSON object : View

Products Affected

f5

nginx_open_source
nginx_ingress_controller
nginx_plus
waf
nginx_instance_manager
dos
nginx_gateway_fabric

CWE

CWE-416

Use After Free

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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.\n\n\n\n\u00a0Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."}], "lastModified": "2026-06-23T13:57:51.283", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:f5:dos:*:*:*:*:*:nginx:*:*", "vulnerable": true, "matchCriteriaId": "0772572C-26F9-4FA4-B9E6-BA40ED59F569", "versionEndIncluding": "4.7.0", "versionStartIncluding": "4.3.0"}, {"criteria": "cpe:2.3:a:f5:dos:4.8.0:*:*:*:*:nginx:*:*", "vulnerable": true, "matchCriteriaId": "C45452BD-7A86-48E7-8E1D-1B340FF70B3B"}, {"criteria": "cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "15B7F1FD-0C49-460F-9CB8-23DA730EC4BE", "versionEndIncluding": "1.6.2", "versionStartIncluding": "1.3.0"}, {"criteria": "cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0A6AA23F-A7A1-43DE-AD67-0EB1249143A4", "versionEndIncluding": "2.6.0", "versionStartIncluding": "2.0.0"}, {"criteria": "cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "10D5B143-4C1E-4626-8B49-3EA7160E9256", "versionEndIncluding": "3.7.2", "versionStartIncluding": "3.5.0"}, {"criteria": "cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "73A1CDBB-49F6-4AB6-AA67-542FD8017D6A", "versionEndIncluding": "4.0.1", "versionStartIncluding": "4.0.0"}, {"criteria": "cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "607EEFA3-BE2A-4660-8C67-E6FC9799325F", "versionEndIncluding": "5.4.2", "versionStartIncluding": "5.0.0"}, {"criteria": "cpe:2.3:a:f5:nginx_instance_manager:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CBC31553-99DE-4155-A8E5-13A84FCCB610", "versionEndIncluding": "2.22.0", "versionStartIncluding": "2.16.0"}, {"criteria": "cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "40EA3893-8D1B-4A72-A600-54025E29DD40", "versionEndIncluding": "1.30.0", "versionStartIncluding": "1.19.0"}, {"criteria": "cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0B153576-468F-48C2-9BC8-922A938AB235", "versionEndIncluding": "r36", "versionStartIncluding": "r32"}, {"criteria": "cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:*", "vulnerable": true, "matchCriteriaId": "F365BA5A-42D7-4024-9143-06D4DEE31212", "versionEndIncluding": "4.16.0", "versionStartIncluding": "4.9.0"}, {"criteria": "cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:*", "vulnerable": true, "matchCriteriaId": "8D720985-9119-480E-929A-7D9D5C083628", "versionEndIncluding": "5.8.0", "versionStartIncluding": "5.1.0"}, {"criteria": "cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:*", "vulnerable": true, "matchCriteriaId": "DE69C522-7FCB-4452-8E33-FCC72D36BF94", "versionEndIncluding": "5.12.1", "versionStartIncluding": "5.9.0"}], "operator": "OR"}]}], "sourceIdentifier": "f5sirt@f5.com"}