The current version of rspamd has a bug in dkim signature validation, which may lead to valid emails being rejected. The issue is found on emails which are sent by MS Exchange 2010 (the specific context is: multiple dkim signatures and simple canonicalization scheme). I've contacted the upstream about the issue and it's fixed in vcs, but it will probably require some time to be released (future 1.6.5?). It might be viable to apply the patch as a gentoo revision bump to fix the issue for other users for now. Bug: https://github.com/vstakhov/rspamd/issues/1841 Patch: https://github.com/vstakhov/rspamd/commit/8dd0d7abaad97d9845f66f7ff814256dd577e072.patch
Upstream fixed this in 1.6.5: https://github.com/vstakhov/rspamd/releases/tag/1.6.5
commit de7467cec1be0ce849106ffd2f8e372bd4af1da0 Author: Christian Roessner <c@roessner.co> Date: Wed Dec 6 21:28:45 2017 +0100 mail-filter/rspamd: version bump to 1.6.5 Package-Manager: Portage-2.3.13, Repoman-2.3.3
