{"id":"CVE-2026-8711","aliases":["ALPINE-CVE-2026-8711","AZL-87117","BELL-CVE-2026-8711","DEBIAN-CVE-2026-8711","EUVD-2026-30940","GHSA-pj32-6rxc-gcmq","UBUNTU-CVE-2026-8711","USN-8425-1"],"status":"published","title":"NGINX JavaScript vulnerability","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","severity":{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.09686,"percentile":0.95543,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-122"],"published":"2026-05-19T14:04:18Z","modified":"2026-11-03T06:33:04Z","fixes":[{"ecosystem":"Alpine:v3.24","package":"nginx","fixed_in":["1.30.2-r1"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"njs","fixed_in":["0.9.9-r0"],"sources":["osv"]},{"ecosystem":"Azure Linux:3","package":"nginx","fixed_in":["1.28.3-4"],"sources":["osv"]},{"ecosystem":"Alpaquita:25","package":"nginx","fixed_in":["1.28.3-r4"],"sources":["osv"]},{"ecosystem":"Alpaquita:stream","package":"nginx","fixed_in":["1.30.2-r1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"libnginx-mod-js","fixed_in":["0.9.9-1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:26.04:LTS","package":"libnginx-mod-js","fixed_in":["0.9.4-1ubuntu0.1~esm1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.24","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.30.2-r1"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"njs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.9.4"},{"fixed":"0.9.9-r0"}]}]},{"source":"osv","ecosystem":"Azure Linux:3","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.28.3-4"}]}]},{"source":"osv","ecosystem":"Alpaquita:25","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.28.0-r3"},{"fixed":"1.28.3-r4"}]}]},{"source":"osv","ecosystem":"Alpaquita:stream","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.22.1-r0"},{"fixed":"1.30.2-r1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"libnginx-mod-js","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.9-1"}]}],"versions":["0.8.9-1","0.9.1-1","0.9.4-1","0.9.6-1","0.9.8-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"libnginx-mod-js","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.9.4-1build2","0.9.9-2","1.0.0-1","1.0.0-3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"libnginx-mod-js","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.4-1ubuntu0.1~esm1"}]}],"versions":["0.9.1-1ubuntu2","0.9.1-1ubuntu3","0.9.4-1~build1","0.9.4-1","0.9.4-1build1","0.9.4-1build2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"libnginx-mod-js","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.4-1ubuntu0.1~esm1"}]}],"versions":["0.9.1-1ubuntu2","0.9.1-1ubuntu3","0.9.4-1~build1","0.9.4-1","0.9.4-1build1","0.9.4-1build2"]}],"products":[{"vendor":"f5","product":"nginx javascript"},{"vendor":"f5","product":"njs"}],"references":[{"url":"https://my.f5.com/manage/s/article/K000161307","tags":["vendor-advisory","Vendor Advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-8711","tags":["web"]},{"url":"https://github.com/advisories/GHSA-pj32-6rxc-gcmq"},{"url":"https://security.alpinelinux.org/vuln/CVE-2026-8711","tags":["advisory"]},{"url":"https://docs.bell-sw.com/security/cves/CVE-2026-8711","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-8711","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-8711","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-8711","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-8425-1","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-8711","title":"NGINX JavaScript vulnerability","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T14:04:18.86Z","modified":"2026-05-21T18:29:16.674Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical","assessor":"cna"},{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T13:48:13.398044Z"}],"euvd":[{"id":"EUVD-2026-30940","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T14:04:18Z","modified":"2026-05-21T18:29:16Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical"}],"updated_at":"2026-11-02T18:21:13.357667Z"}],"ghsa":[{"id":"GHSA-pj32-6rxc-gcmq","title":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at...","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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, for systems with Address Space Layout Randomization (ASLR) disabled, code execution is possible. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T15:31:36Z","modified":"2026-05-19T15:31:44Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical"},{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T15:08:12.004262Z"}],"nvd":[{"id":"CVE-2026-8711","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T15:16:33.017Z","modified":"2026-07-23T20:10:00.13Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical","assessor":"secondary"},{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T14:12:19.752984Z"}],"osv":[{"id":"ALPINE-CVE-2026-8711","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T15:16:33.017Z","modified":"2026-11-03T06:33:04.19297485Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-03T07:15:37.282377Z"},{"id":"BELL-CVE-2026-8711","status":"published","published":"2026-05-22T06:12:25.171751Z","modified":"2026-06-06T07:15:05.88808961Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:28:26.630331Z"},{"id":"CVE-2026-8711","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T15:16:33.017Z","modified":"2026-10-24T10:30:19.542534668Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:45:19.210277Z"},{"id":"DEBIAN-CVE-2026-8711","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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.","status":"published","published":"2026-05-19T15:16:33.017Z","modified":"2026-10-01T03:03:51.311814227Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:46:05.022702Z"},{"id":"UBUNTU-CVE-2026-8711","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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.","status":"published","published":"2026-05-19T15:16:00Z","modified":"2026-10-17T13:01:14.273355881Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"},{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical"}],"updated_at":"2026-11-02T16:57:24.828975Z"},{"id":"AZL-87117","title":"CVE-2026-8711 affecting package nginx for versions less than 1.28.3-4","description":"NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","status":"published","published":"2026-05-19T15:16:33Z","modified":"2026-09-22T05:34:53Z","updated_at":"2026-11-02T15:28:10.677811Z"},{"id":"USN-8425-1","title":"libnginx-mod-js vulnerability","description":"It was discovered that njs did not properly handle certain client-\ncontrolled variables when processing ngx.fetch() requests. An attacker\ncould possibly use this issue to trigger a heap buffer overflow, resulting\nin arbitrary code execution or a denial of service.","status":"published","published":"2026-06-11T20:54:04Z","modified":"2026-06-18T00:44:22.51208462Z","updated_at":"2026-11-02T16:58:25.103481Z"}]}}