{"id":"USN-8563-4","aliases":[],"status":"published","title":"nginx regression","description":"USN-8563-3 fixed a vulnerability in nginx. The fix introduced a regression\nin certain environments. This update reverts the fix for CVE-2026-42533\npending further investigation.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n It was discovered that nginx incorrectly handled certain map directives\n using regex matching and capture variables. A remote attacker could use\n this issue to cause nginx to crash, resulting in a denial of service, or\n possibly execute arbitrary code. (CVE-2026-42533)\n\n It was discovered that nginx had a use-after-free vulnerability in the\n ngx_http_ssi_module module when configured with Server-Side Includes,\n proxy_pass, and proxy buffering disabled directives. An attacker able to\n intercept traffic and control responses from an upstream server could\n possibly use this issue to cause nginx to crash, resulting in a denial of\n service. (CVE-2026-56434)\n\n It was discovered that nginx incorrectly handled certain requests in the\n ngx_http_slice_module module. A remote attacker could possibly use this\n issue to obtain sensitive information or cause nginx to crash, resulting\n in a denial of service. (CVE-2026-60005)","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2026-08-19T19:30:43Z","modified":"2026-08-20T05:15:04Z","fixes":[{"ecosystem":"Ubuntu:22.04:LTS","package":"nginx","fixed_in":["1.18.0-6ubuntu14.20"],"sources":["osv"]},{"ecosystem":"Ubuntu:24.04:LTS","package":"nginx","fixed_in":["1.24.0-2ubuntu7.17"],"sources":["osv"]},{"ecosystem":"Ubuntu:26.04:LTS","package":"nginx","fixed_in":["1.28.3-2ubuntu1.10"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.18.0-6ubuntu14.20"}]}],"versions":["1.18.0-6ubuntu11","1.18.0-6ubuntu12","1.18.0-6ubuntu14","1.18.0-6ubuntu14.1","1.18.0-6ubuntu14.2","1.18.0-6ubuntu14.3","1.18.0-6ubuntu14.4","1.18.0-6ubuntu14.5","1.18.0-6ubuntu14.6","1.18.0-6ubuntu14.7","1.18.0-6ubuntu14.8","1.18.0-6ubuntu14.10","1.18.0-6ubuntu14.11","1.18.0-6ubuntu14.12","1.18.0-6ubuntu14.13","1.18.0-6ubuntu14.14","1.18.0-6ubuntu14.15","1.18.0-6ubuntu14.16","1.18.0-6ubuntu14.17","1.18.0-6ubuntu14.18","1.18.0-6ubuntu14.19"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.24.0-2ubuntu7.17"}]}],"versions":["1.24.0-1ubuntu1","1.24.0-2ubuntu1","1.24.0-2ubuntu2","1.24.0-2ubuntu3","1.24.0-2ubuntu4","1.24.0-2ubuntu6","1.24.0-2ubuntu7","1.24.0-2ubuntu7.1","1.24.0-2ubuntu7.3","1.24.0-2ubuntu7.4","1.24.0-2ubuntu7.5","1.24.0-2ubuntu7.6","1.24.0-2ubuntu7.7","1.24.0-2ubuntu7.8","1.24.0-2ubuntu7.9","1.24.0-2ubuntu7.10","1.24.0-2ubuntu7.11","1.24.0-2ubuntu7.12","1.24.0-2ubuntu7.13","1.24.0-2ubuntu7.14","1.24.0-2ubuntu7.15","1.24.0-2ubuntu7.16"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"nginx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.28.3-2ubuntu1.10"}]}],"versions":["1.28.0-6ubuntu1","1.28.1-2ubuntu1","1.28.1-3ubuntu1","1.28.2-2ubuntu1","1.28.3-2ubuntu1","1.28.3-2ubuntu1.1","1.28.3-2ubuntu1.2","1.28.3-2ubuntu1.3","1.28.3-2ubuntu1.4","1.28.3-2ubuntu1.5","1.28.3-2ubuntu1.6","1.28.3-2ubuntu1.7","1.28.3-2ubuntu1.8","1.28.3-2ubuntu1.9"]}],"references":[{"url":"https://ubuntu.com/security/notices/USN-8563-4","tags":["advisory"]},{"url":"https://bugs.launchpad.net/bugs/2164558","tags":["report"]}],"sources":{"osv":[{"id":"USN-8563-4","title":"nginx regression","description":"USN-8563-3 fixed a vulnerability in nginx. The fix introduced a regression\nin certain environments. This update reverts the fix for CVE-2026-42533\npending further investigation.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n It was discovered that nginx incorrectly handled certain map directives\n using regex matching and capture variables. A remote attacker could use\n this issue to cause nginx to crash, resulting in a denial of service, or\n possibly execute arbitrary code. (CVE-2026-42533)\n\n It was discovered that nginx had a use-after-free vulnerability in the\n ngx_http_ssi_module module when configured with Server-Side Includes,\n proxy_pass, and proxy buffering disabled directives. An attacker able to\n intercept traffic and control responses from an upstream server could\n possibly use this issue to cause nginx to crash, resulting in a denial of\n service. (CVE-2026-56434)\n\n It was discovered that nginx incorrectly handled certain requests in the\n ngx_http_slice_module module. A remote attacker could possibly use this\n issue to obtain sensitive information or cause nginx to crash, resulting\n in a denial of service. (CVE-2026-60005)","status":"published","published":"2026-08-19T19:30:43Z","modified":"2026-08-20T05:15:04.273973182Z","updated_at":"2026-11-02T16:58:25.103481Z"}]}}