Tag
IoT
all chapters
- Chapter 3 The botnet that left its code out in the open Another one walks in and drops its critter. But this one left a door open on its own delivery server - and inside was the source code. A multi-architecture Mirai, caught red-handed.
- Chapter 11 The bot that bragged - and couldn't be bothered A 1,177-byte loader landed: nine lines of wget, one per architecture, in the style I have already opened three times on this blog. I was going to file it as a repeat offender and get on with my day. I opened it anyway, out of habit - and the first thing I saw was that it had a few characters too many.
- Chapter 17 Fresh out of the oven A quiet Sunday, my new-binary alarm went off after days of silence. The first thought was the best one there is: something fresh. What followed was a rollercoaster - an old acquaintance, a false positive that nearly fooled me, and finally a critter that wasn't in any public repository, caught less than thirty hours after it was born.
- Chapter 18 Nothing to file An already-infected IP connected to the honeypot's telnet and pasted a recipe all at once: eleven binaries, one per architecture, each with a made-up name that will never come round again. Two weighed exactly the same and looked like variants - they turned out to be the i586 and i686 builds of the same program. And behind them wasn't a stray bug: fifty-odd distinct binaries in two weeks. The whole delivery is built so that no blocklist, by name or by signature, catches anything.
- Chapter 19 A Mirai that couldn't attack? I pulled down the three binaries from the previous chapter expecting the usual DDoS arsenal. It wasn't there: not one attack function. What it does instead (and above all, the channel its orders arrive on) is the strangest thing that has come through the honeypot. A bug designed, top to bottom, not to be seen.
- Chapter 21 Introduced by its enemy An automated scanner found the honeypot's telnet and, eighteen seconds later, there was a binary inside. The password was «telnet». The loader it dropped comes with two operator typos, one of which breaks an entire infection. And when I finally put a name to the family (IranBot, a Mirai fork with a public dossier) it turned out that name had been written on this blog since August: a rival bot had put it there, in the list of competitors it uninstalls on arrival.
- Chapter 29 It told me its name three times Another IoT ELF with the look of a run-of-the-mill Mirai landed in the decoy. I christened it “zbot” after its cron files, and it turned out that wasn’t even its name: by three separate routes (the paths it left on disk, the banners it speaks SSH and HTTP with, and the first bytes of every message to its C2) the thing kept telling me its real name. Behind it was something more interesting than a server-flooding bot: a machine for renting out its victim’s home line as a proxy. And an operator who, with the whole thing built, kept breaking his own download URLs. XLab had already named it “Shemzbot” in a tweet; this is the teardown that tweet didn’t carry.
- Chapter 30 The C2's Landlord Last chapter I opened shem up from the inside, but one thing nagged at me: its command centre is a bare IP, no domain, so I couldn't follow the operator. I pulled on that IP anyway. And what turns up at the other end isn't the operator - it's his landlord: a bulletproof hosting block that swaps its name and its plates to stay out of reach, rents to half a dozen botnets at once, and throws the server away after ten days.
- Chapter 31 One door, three visitors Forty megabytes of binary that won't open: the decompiler takes one look and refuses. Before forcing that door, the boring part that has to come first - who brought them here.
- Chapter KHserver