Opportunistic Encryption in HTTP2 could be used to bypass the Same-Origin-Policy on services hosted on other ports - CVE-2021-38507ID: oval:org.secpod.oval:def:75778 | Date: (C)2021-11-04 (M)2023-11-19 |
Class: VULNERABILITY | Family: macos |
Mozilla Firefox 94, Mozilla Firefox ESR 91.3 and Thunderbird 91.3 : 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. However, if a second encrypted port on the same IP address (e.g. port 8443) did not opt-in to opportunistic encryption; a network attacker could forward a connection from the browser to port 443 to port 8443, causing the browser to treat the content of port 8443 as same-origin with HTTP. This was resolved by disabling the Opportunistic Encryption feature, which had low usage.
Platform: |
Apple Mac OS 14 |
Apple Mac OS 13 |
Apple Mac OS 12 |
Apple Mac OS X 10.11 |
Apple Mac OS X 10.12 |
Apple Mac OS X 10.13 |
Apple Mac OS X 10.14 |
Apple Mac OS X 10.15 |
Apple Mac OS 11 |
Product: |
Mozilla Firefox |
Mozilla Firefox ESR |
Mozilla Thunderbird |