Topic starter
02/08/2026 12:31 pm
TL;DR: RomCom used a patched WinRAR path traversal flaw to deliver backdoors through phishing RAR files, hiding payloads with alternate data streams and Startup-folder persistence while ESET tracked job-application lures across Europe and Canada, according to Anomali. Archive-based delivery still works because user trust, manual patching, and weak file handling controls remain exploitable.
Editorial analysis by NHI Mgmt Group, based on content published by Anomali: “Anomali Cyber Watch: WinRAR Malware, Erlang OTP Exploitation, Charon Ransomware, and More”.
Key questions
Q: What breaks when archive extraction can write outside the intended folder?
A: Path traversal turns a normal archive into an arbitrary file dropper.
Q: Why does delayed patching make archive malware campaigns more effective?
A: Because attackers can work against the gap between disclosure and actual deployment.
Q: What are the signs that archive-based persistence is being used?
A: Look for suspicious LNK files in Startup locations, unexpected executable drops in %TEMP%, and archive contents that contain misleading or excessive path entries.
Practitioner guidance
- Harden archive extraction paths Restrict where archive utilities can write extracted content and block any attempt to place files into autorun or startup-sensitive locations.
- Inspect for hidden archive artefacts Scan extracted archives for alternate data streams, unexpected nested paths, and executable drops that do not match the apparent file tree.
- Monitor Windows Startup persistence Alert on new LNK files or other persistence artefacts created in Startup folders after archive activity, especially when users report job-application mailings.
Bottom line: Archive abuse works because extraction can be manipulated into file placement, persistence, and execution, not because the phishing lure is sophisticated.
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02/08/2026 1:28 pm
Archive abuse remains effective because file handling is still treated as a low-risk control point. The WinRAR case shows that extraction logic, not just email filtering, sits on the attacker path. When a compressed file can write into execution locations, the archive becomes a delivery mechanism rather than a passive container. Practitioners should treat archive handling as part of endpoint and email governance, not a file utility problem.
A question worth separating out:
Q: Should teams treat archive abuse differently from ordinary phishing attachments?
A: Yes. Archive abuse is not just about the lure that delivered it, but about what the extraction process can do after the user opens it. Teams should combine email filtering with endpoint controls that inspect extraction behaviour, block risky write locations, and watch for persistence mechanisms. The difference is in post-delivery capability, not the lure alone.
👉 Read our full editorial: WinRAR malware and phishing lures show how archive abuse persists