{"attribution":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","cve":{"id":"CVE-2026-56434","sourceIdentifier":"f5sirt@f5.com","published":"2026-07-15T15:16:45.700","lastModified":"2026-08-10T15:27:56.373","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process.\n\nImpact:\nThis vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only.\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated."}],"affected":[{"source":"f5sirt@f5.com","affectedData":[{"vendor":"F5","product":"NGINX Plus","defaultStatus":"unknown","modules":["ngx_http_ssi_module"],"versions":[{"version":"37.0.0.1","lessThan":"37.0.3.1","versionType":"custom","status":"affected"},{"version":"R36","lessThan":"R36 P7","versionType":"custom","status":"affected"},{"version":"R33","lessThan":"*","versionType":"custom","status":"affected"}]},{"vendor":"F5","product":"NGINX Open 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Advisory"]}]}}