Patches are now available for 5.6 and 5.7 which fix an smtpd errata. 5.6 errata 25 and 5.7 errata 8: Fix multiple reliability issues in smtpd: a local user can cause smtpd to fail by writing an invalid imsg to control socket. a local user can prevent smtpd from serving new requests by exhausting descriptors.
Links: http://www.openbsd.org/errata56.html http://ftp.openbsd.org/pub/OpenBSD/patches/5.6/common/025_smtpd.patch.sig http://www.openbsd.org/errata57.html http://ftp.openbsd.org/pub/OpenBSD/patches/5.7/common/008_smtpd.patch.sig -- Gilles Chehade https://www.poolp.org @poolpOrg
