{"id":"ALPINE-CVE-2021-21703","details":"In PHP versions 7.3.x up to and including 7.3.31, 7.4.x below 7.4.25 and 8.0.x below 8.0.12, when running PHP FPM SAPI with main FPM daemon process running as root and child worker processes running as lower-privileged users, it is possible for the child processes to access memory shared with the main process and write to it, modifying it in a way that would cause the root process to conduct invalid memory reads and writes, which can be used to escalate privileges from local unprivileged user to the root user.","modified":"2026-11-03T06:32:27.377460465Z","published":"2021-10-25T06:15:06.563Z","upstream":["CVE-2021-21703"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2021-21703"}],"affected":[{"package":{"name":"php7","ecosystem":"Alpine:v3.12","purl":"pkg:apk/alpine/php7?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.3.32-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php7","ecosystem":"Alpine:v3.13","purl":"pkg:apk/alpine/php7?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.4.25-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php7","ecosystem":"Alpine:v3.14","purl":"pkg:apk/alpine/php7?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.4.25-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php7","ecosystem":"Alpine:v3.15","purl":"pkg:apk/alpine/php7?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.4.25-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php8","ecosystem":"Alpine:v3.13","purl":"pkg:apk/alpine/php8?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.12-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php8","ecosystem":"Alpine:v3.14","purl":"pkg:apk/alpine/php8?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.12-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php8","ecosystem":"Alpine:v3.15","purl":"pkg:apk/alpine/php8?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.12-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php8","ecosystem":"Alpine:v3.16","purl":"pkg:apk/alpine/php8?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.12-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php81","ecosystem":"Alpine:v3.16","purl":"pkg:apk/alpine/php81?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.1.0_rc5-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php81","ecosystem":"Alpine:v3.17","purl":"pkg:apk/alpine/php81?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.1.0_rc5-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php81","ecosystem":"Alpine:v3.18","purl":"pkg:apk/alpine/php81?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.1.0_rc5-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}},{"package":{"name":"php81","ecosystem":"Alpine:v3.19","purl":"pkg:apk/alpine/php81?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.1.0_rc5-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-21703.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}