{"id":"CVE-2026-42945","published":"2026-05-13T14:12:43Z","modified":"2026-09-10T12:04:53Z","title":"NGINX ngx_http_rewrite_module vulnerability","vendor":"F5","product":"NGINX Plus","tier":"core","eol":null,"affectedVersions":[{"vendor":"F5","product":"NGINX Plus","versions":[">= R36, < R36 P4",">= R32, < R32 P6"]},{"vendor":"F5","product":"NGINX Open Source","versions":[">= 0.6.27, < 1.30.1"]}],"description":{"text":"NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Expression (PCRE) capture (for example, $1, $2) with a replacement string that includes a question mark (?). An unauthenticated attacker along with conditions beyond its control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","provenance":"source","from":"CVE.org"},"summary":{"text":"The flaw is a heap buffer overflow in the ngx_http_rewrite_module of F5's NGINX Plus and NGINX Open Source. It occurs when a rewrite directive is followed by a rewrite, if, or set directive that uses an unnamed PCRE capture (such as $1 or $2) with a replacement string containing a question mark. An unauthenticated remote attacker can trigger it by sending crafted HTTP requests, though it requires conditions outside the attacker's control; this can crash the NGINX worker process, and code execution is possible where ASLR is disabled or can be bypassed.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-29T07:11:53Z"},"cvss":{"score":8.1,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"CVE.org CNA"},"epss":{"score":0.68047,"percentile":0.99324,"date":"2026-10-30","provenance":"source"},"kev":null,"vulncheckKev":{"dateAdded":"2026-05-16","exploitedFirstSeen":"2026-05-16","ransomware":false,"evidence":[{"url":"https://www.linkedin.com/posts/patrickmgarrity_cybersecurity-threatintelligence-riskmanagement-share-7461369931851517952-PBjV/","date":"2026-05-16"},{"url":"https://hunt.io/blog/open-directory-nginx-rift-ghost-cms-multi-cve","date":"2026-07-20"}],"evidenceTotal":2,"provenance":"source"},"exploited":true,"otx":{"pulseCount":6,"pulses":[{"name":"Known_Cve | May 22, 2026","url":"https://otx.alienvault.com/pulse/6a0f13fd08d4602f56683eec","created":"2026-05-21"},{"name":"Known_Cve | May 21, 2026","url":"https://otx.alienvault.com/pulse/6a0dc2491bcde0bdb3d7e14e","created":"2026-05-20"},{"name":"Known_Cve | May 20, 2026 | Part 1/2","url":"https://otx.alienvault.com/pulse/6a0c70e0012db9b5d3f1491b","created":"2026-05-19"},{"name":"Known_Cve | May 19, 2026 | Part 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Size"}],"references":[{"url":"https://my.f5.com/manage/s/article/K000161019","tags":["vendor-advisory","patch"]},{"url":"https://depthfirst.com/nginx-rift","tags":[]},{"url":"https://github.com/DepthFirstDisclosures/Nginx-Rift","tags":[]},{"url":"https://access.redhat.com/security/cve/CVE-2026-42945","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2477116","tags":["issue-tracking","x_refsource_REDHAT"]},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42945.json","tags":["x_sadp-csaf-vex"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17790","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:18063","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:19159","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:18041","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17791","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17751","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17792","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17793","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17752","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17794","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17753","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:18029","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:19371","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:19374","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:19372","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:17417","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22396","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22393","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22394","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22390","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22388","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22389","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22383","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22382","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:20442","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:20444","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:58981","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:21275","tags":["vendor-advisory","x_refsource_REDHAT"]}],"techniques":[],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2026-30010","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-30010","exploited":false,"exploitedSince":null,"provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":38,"skipped":9,"earliest":"2026-05-14","earliestUrl":"https://github.com/friparia/NGINX_RIFT_SCAN_CVE_2026_42945","repos":[{"name":"cipherspy/CVE-2026-42945-POC","url":"https://github.com/cipherspy/CVE-2026-42945-POC","stars":64,"created":"2026-05-14"},{"name":"friparia/NGINX_RIFT_SCAN_CVE_2026_42945","url":"https://github.com/friparia/NGINX_RIFT_SCAN_CVE_2026_42945","stars":34,"created":"2026-05-14"},{"name":"MateusVerass/nGixshell","url":"https://github.com/MateusVerass/nGixshell","stars":27,"created":"2026-05-16"},{"name":"rheodev/CVE-2026-42945","url":"https://github.com/rheodev/CVE-2026-42945","stars":24,"created":"2026-05-14"},{"name":"oseasfr/Scanner_CVE_2026-42945","url":"https://github.com/oseasfr/Scanner_CVE_2026-42945","stars":19,"created":"2026-05-15"}]},"first":{"date":"2026-05-14","source":"PoC-in-GitHub","url":"https://github.com/friparia/NGINX_RIFT_SCAN_CVE_2026_42945"},"provenance":"source"},"exploitRefs":[],"flow":[],"timeline":[{"date":"2026-05-13","kind":"published","label":"Published 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