CVE-2026-40701mediumCWE-416

CVE-2026-40701: medium-severity vulnerability in F5 NGINX Plus

NGINX ngx_http_ssl_module vulnerability

Published

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 6.3epss 0.7%
from disclosure to weapon15 days
Published on NVDMay 13
1st PoC+15d
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:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
F5 · NGINX Open SourceF5 · NGINX Plus
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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