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Developing secure software is a challenge. Writing really secure software is a real challenge.
Here are the articles which touch different security aspects of software, from “what cipher suites are not to be used with TLS”, to certain more or less novel things under ‘Security Research’ subcategory.

All Software Herecies about Security, page 1:

Direct Payment Processing. Recovery from ‘Unknown’ Transaction Status. PCI DSS.

Quote: “With the Direct Processing, customer should trust us (the merchant) with their details”
Another Quote: “On the other hand, most of PCI DSS requirements make perfect sense regardless of formal compliance”
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Payment Processing. Credit Cards. Chargebacks and Collateral Damage

Quote: “Chargeback monster will come from under the bed and will eat all your hard-earned money!”
Another Quote: “it is trivial to develop a system with guaranteed zero chargeback rate – to achieve this, it is sufficient to decline each and every transaction at pre-filter stage”
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War on Clones, Part II. Identifying Mobile and Browsers. Social and Payment-Based Identification. Putting it all together.

Quote: “as much as iOS is a device identification nightmare, Android is a device identification paradise.”
Another Quote: “Everybody makes occasional mistakes, cheaters/abusers included.”
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War on Clones, Part I. IP-based (non-)Identification. Identifying PCs and Macs

Quote: “NEVER EVER use IPv4 for long-term bans”
Another Quote: “If using MAC addresses to identify devices, you SHOULD gather stats on repeating MAC addresses within your DB”
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Random Number Generation

Quote: “even if your RNG is statistically perfect, people will still complain 🙁 “
Another Quote: “On modern x86 CPUs, single core can generate 150M+ random bytes/second this way (and this is a Damn Lot).”
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