{"id":"ALPINE-CVE-2021-28363","details":"The urllib3 library 1.26.x before 1.26.4 for Python omits SSL certificate validation in some cases involving HTTPS to HTTPS proxies. The initial connection to the HTTPS proxy (if an SSLContext isn't given via proxy_config) doesn't verify the hostname of the certificate. This means certificates for different servers that still validate properly with the default urllib3 SSLContext will be silently accepted.","modified":"2026-03-09T01:21:43.832582Z","published":"2021-03-15T18:15:19.017Z","upstream":["CVE-2021-28363"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2021-28363"}],"affected":[{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.14","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.15","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.16","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.17","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.18","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.19","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.20","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6-r0","1.25.6-r1","1.25.7-r0","1.25.7-r1","1.25.8-r0","1.25.9-r0","1.26.0-r0","1.26.1-r0","1.26.2-r0","1.26.2-r1","1.26.3-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2021-28363.json"}},{"package":{"name":"py3-urllib3","ecosystem":"Alpine:v3.21","purl":"pkg:apk/alpine/py3-urllib3?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.4-r0"}]}],"versions":["1.18-r0","1.21.1-r0","1.22-r0","1.24.1-r0","1.24.1-r1","1.24.2-r0","1.25.1-r0","1.25.10-r0","1.25.11-r0","1.25.2-r0","1.25.3-r0","1.25.5-r0","1.25.6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