Fake 7zip.com installer turns Windows PCs into residential proxy nodes
A spoofed 7zip.com installer is being used to compromise Windows machines and enroll them into residential proxy networks.
Security researchers have documented a campaign abusing a convincing lookalike domain for the popular 7‑Zip utility.
## What happened
- Attackers used 7zip[.]com to distribute a trojanized 7‑Zip installer (the legitimate project is hosted at 7-zip.org).
- The installer delivers a working 7‑Zip File Manager to avoid suspicion, while silently dropping additional components into `C:\Windows\SysWOW64\hero\`.
## What the malware does
- Establishes persistence by registering auto-start Windows services.
- Manipulates firewall rules via `netsh` to allow its binaries.
- Profiles the host via WMI/Windows APIs.
- Enrolls the machine as a residential proxy node, enabling third parties to route traffic through the victim’s IP.
## Why it matters
Proxyware infections can be “quiet” but harmful: they can degrade performance, create privacy risk, and get the victim’s IP reputation burned by abuse routed through it (fraud, scraping, ad abuse).
## Defensive guidance
- Treat systems that executed installers from 7zip.com as compromised and investigate.
- Check for suspicious services and binaries under the `hero` directory.
- Reinstall from trusted sources and consider OS rebuild for high-risk environments.
Source: Malwarebytes