This is an automated email from the git hooks/post-receive script.
richard pushed a commit to branch tor-browser-91.13.0esr-11.5-1 in repository tor-browser.
commit 5eba1842a0124ea28e7f211d7cb6fdb1793e6e3b Author: Richard Pospesel richard@torproject.org AuthorDate: Thu Aug 4 09:00:02 2022 +0000
fixup! Firefox preference overrides.
Bug 27719: Treat unsafe renegotiation as broken --- browser/app/profile/001-base-profile.js | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/browser/app/profile/001-base-profile.js b/browser/app/profile/001-base-profile.js index 79538d3e809ee..2752e95313751 100644 --- a/browser/app/profile/001-base-profile.js +++ b/browser/app/profile/001-base-profile.js @@ -64,6 +64,18 @@ pref("media.memory_cache_max_size", 16384); pref("dom.security.https_only_mode", true); pref("dom.security.https_only_mode.upgrade_onion", false);
+// Require Safe Negotiation ( https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/27719 ) +// Blocks connections to servers that don't support RFC 5746 [2] as they're potentially vulnerable to a +// MiTM attack [3]. A server without RFC 5746 can be safe from the attack if it disables renegotiations +// but the problem is that the browser can't know that. Setting this pref to true is the only way for the +// browser to ensure there will be no unsafe renegotiations on the channel between the browser and the server +// [STATS] SSL Labs (July 2021) reports over 99% of top sites have secure renegotiation [4] +// [1] https://wiki.mozilla.org/Security:Renegotiation +// [2] https://datatracker.ietf.org/doc/html/rfc5746 +// [3] https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3555 +// [4] https://www.ssllabs.com/ssl-pulse/ +pref("security.ssl.require_safe_negotiation", true); + // Misc privacy: Remote pref("browser.send_pings", false); pref("geo.enabled", false);