7MS #733: Tales of Pentest Pwnage – Part 87

Hey friends! Today's episode comes to you from a parking lot in the rain, with a mint hot cocoa in hand and your host absolutely dragging his butt (D-R-A-G-G-I-N-G, not D-R-A-G-O-N – I've never seen a dragon's butt and can't speak to how mine compares). I've had a bunch of internals back to back lately and I'm basically a drooling dog who found a frisbee and refuses to put it down. Sleep be darned.

So instead of walking through one test start to finish, I want to share a few things that have helped me claw out a foothold in environments that are otherwise really locked down:

The "good problem" of a mature client – several of these engagements are third- or fourth-year tests, and the clients actually clear findings off the board. Which is great for them and rough for me, because this year's test shouldn't look anything like last year's. All my favorite go-tos came up empty – machine account quota set to zero, no broadcast traffic tomfoolery (Responder and mitm6 got me nothing), SMB signing on everywhere, ADCS either absent or buttoned up, and a low-priv account that BloodHound says has zero interesting permissions and zero local admin anywhere. Cool cool cool. When the network's clean, go file-hunting – which means firing up Snaffler and letting it comb the shares. Normally that wraps up in about an hour. On these engagements it was running three and four hours. Then Windows told me I was out of disk – I like having Snaffler pull down copies of interesting files so I can review them locally instead of authenticating to each share. Turns out it had grabbed 50-60 gigs and left me with about eight gigs of breathing room. Tip #1: put a 1 TB drive in your drop boxes – I ran with tiny drives for years early in the 7MS days and it was always a pinch. Beyond situations like this one, sometimes you find a giant backup file or VMDK on a share and you need somewhere to put it so you can crack it open and go shopping. Tip #2: you can grow a VM disk on the fly – in Proxmox you can resize the disk on a running VM, then hop into Disk Management inside Windows and extend the C drive. Instant elbow room, no downtime. Death by a million tiny files – the real culprit was one file extension I should have excluded, and the client had hundreds of thousands of them. Rather than restart a run I was already hours into, I had AI whip up a little PowerShell loop that swept the Snaffler dump folder every 10 minutes and deleted the extensions I didn't care about. Woke up the next mor