On 4/24/2015 9:38 AM, Reindl Harald wrote:
Am 24.04.2015 um 15:22 schrieb Dianne Skoll:
On Fri, 24 Apr 2015 15:17:45 +0200
Reindl Harald <h.rei...@thelounge.net> wrote:
v=spf1 exists:gmail.com -all
makes no sense - the spammer don't own the domain in most cases and
if they do then they just don't add a SPF policy to use it with
infected clients
Spammers often register and use throwaway domains. And check how the
exists: mechanism works
well, and how becomes SPF part of the game in case of a throw-away
domain as long as "score SPF_NONE 0" - why in the world should a
spammer add a TXT record to a throw-away domain?
Because passing SPF causes other checks to not trigger. For instance,
KAM.cf has a lot of rules that meta on KAM_LAZY_DOMAIN_SECURITY. The
default spamassassin rules also meta extensively on SPF failure, via
__NOT_SPOOFED.
