If a server sends two Strict-Transport-Security (STS) headers for a single connection, they will be rejected as invalid and HTTP Strict Transport Security (HSTS) will not be enabled for the connection. This vulnerability affects Firefox < 55.
{ "binaries": [ { "binary_version": "55.0.1+build2-0ubuntu0.14.04.2", "binary_name": "firefox" }, { "binary_version": "55.0.1+build2-0ubuntu0.14.04.2", "binary_name": "firefox-dev" }, { "binary_version": "55.0.1+build2-0ubuntu0.14.04.2", "binary_name": "firefox-globalmenu" }, { "binary_version": "55.0.1+build2-0ubuntu0.14.04.2", "binary_name": "firefox-mozsymbols" }, { "binary_version": "55.0.1+build2-0ubuntu0.14.04.2", "binary_name": "firefox-testsuite" } ], "availability": "No subscription required" }
{ "binaries": [ { "binary_version": "55.0.1+build2-0ubuntu0.16.04.2", "binary_name": "firefox" }, { "binary_version": "55.0.1+build2-0ubuntu0.16.04.2", "binary_name": "firefox-dev" }, { "binary_version": "55.0.1+build2-0ubuntu0.16.04.2", "binary_name": "firefox-globalmenu" }, { "binary_version": "55.0.1+build2-0ubuntu0.16.04.2", "binary_name": "firefox-mozsymbols" }, { "binary_version": "55.0.1+build2-0ubuntu0.16.04.2", "binary_name": "firefox-testsuite" } ], "availability": "No subscription required" }