* [Blog](https://www.paloaltonetworks.com/blog) * [Palo Alto Networks](https://www.paloaltonetworks.com/blog/corporate/) * Blacklists # Palo Alto Networks ## Blacklists [![Can I spam from here: An Unusually Clever Spambot Tests Blacklists](https://www.paloaltonetworks.com/blog/wp-content/uploads/2016/09/unit42-web-banner-650x300.jpg)](https://www.paloaltonetworks.com/blog/2016/10/unit42-can-i-spam-from-here-an-unusually-clever-spambot-tests-blacklists/) [Can I spam from here: An Unusually Clever Spambot Tests Blacklists \------------------------------------------------------------------](https://www.paloaltonetworks.com/blog/2016/10/unit42-can-i-spam-from-here-an-unusually-clever-spambot-tests-blacklists/) Unit 42 researchers recently observed an unusually clever spambot's attempts to increase delivery efficacy by abusing reputation blacklist service APIs. Rather than sending spam as soon as the host is infected, the bot checks common blacklists to confirm its e-mails will actually be delivered, and if not, shuts itself down. This... [Unit 42](https://unit42.paloaltonetworks.com) Oct 19, 2016 By [Brandon Levene](https://www.paloaltonetworks.com/blog/author/brandon-levene/?ts=markdown "Posts by Brandon Levene") and [Brandon Young](https://www.paloaltonetworks.com/blog/author/brandon-young/?ts=markdown "Posts by Brandon Young") ## Palo Alto Networks *** ** * ** *** [Announcements](https://www.paloaltonetworks.com/blog/category/announcement/?ts=markdown) *** ** * ** *** [Company \& Culture](https://www.paloaltonetworks.com/blog/category/company-culture/?ts=markdown) *** ** * ** *** [Points of View](https://www.paloaltonetworks.com/blog/category/points-of-view/?ts=markdown) *** ** * ** *** [Public Sector](https://www.paloaltonetworks.com/blog/category/public-sector/?ts=markdown) *** ** * ** *** [Products and Services](https://www.paloaltonetworks.com/blog/category/products-and-services/?ts=markdown) *** ** * ** *** [Partners](https://www.paloaltonetworks.com/blog/category/partners/?ts=markdown) *** ** * ** *** ### Subscribe to the Blog! 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