{"id":"CLEANSTART-2024-YS57327","summary":"Opportunistic Encryption feature of HTTP2 (RFC 8164) allows a connection to be transparently upgraded to TLS while retaining the visual properties of an HTTP connection, including being same-origin...","details":"CVE-2021-38507 affects multiple packages. The Opportunistic Encryption feature of HTTP2 (RFC 8164) allows a connection to be transparently upgraded to TLS while retaining the visual properties of an HTTP connection, including being same-origin with unencrypted connections on port 80. See references for individual vulnerability details.","modified":"2026-10-31T01:00:55.315334335Z","published":"2026-10-30T19:19:12.577828Z","upstream":["CVE-2021-38507"],"database_specific":{},"references":[{"type":"ADVISORY","url":"https://github.com/cleanstart-dev/cleanstart-security-advisories/tree/main/advisories/2024/CLEANSTART-2024-YS57327.json"},{"type":"WEB","url":"https://osv.dev/vulnerability/CVE-2021-38507"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-38507"}],"affected":[{"package":{"name":"firefox","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox?arch=x86_64"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"94.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox?arch=armv7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"94.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox?arch=aarch64"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"94.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox?arch=x86"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"94.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox?arch=ppc64le"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"94.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox-esr","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox-esr?arch=x86_64"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"91.3.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox-esr","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox-esr?arch=armv7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"91.3.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox-esr","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox-esr?arch=aarch64"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"91.3.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox-esr","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox-esr?arch=x86"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"91.3.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}},{"package":{"name":"firefox-esr","ecosystem":"CleanStart","purl":"pkg:apk/cleanstart/firefox-esr?arch=ppc64le"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"91.3.0-r0"}]}],"database_specific":{"source":"https://github.com/cleanstart-dev/cleanstart-security-advisories/blob/main/advisories/2024/CLEANSTART-2024-YS57327.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N"}]}