AntiFox-linked intrusions used IIS web shells and valid AWS credentials
Arctic Wolf Labs linked AntiFox-hosting infrastructure to intrusions involving internet-facing IIS applications and AWS customer accounts. Investigators observed successful access to a production secret and, in separate activity, S3 object reads, copies and deletions.
- Disclosed
- Nov 10, 2026
- Public disclosure date
- Severity
- Sharted
- No CVE: a breach, not a bug
- Splash zone
- Compromised internet-facing IIS applications and AWS customer accounts accessed with valid IAM credentials or role sessions.
- AntiFox · IIS · AWS · credentials
- In the wild
- Yes
- Arctic Wolf observed live intrusions and successful AWS API calls.
What happened
Arctic Wolf observed an IIS worker write an ASPX web shell and run commands that extracted application settings and database connection strings. The initial IIS vulnerability is unknown. In other activity the attacker started with a valid AWS credential whose origin was unknown. The cloud actions occurred inside customer environments using existing AWS identities. The researchers did not identify a victim count or attribute every action to an AI agent.
Crime-scene timeline
Nov 10, 16:41 UTC
Arctic Wolf Labs publishes its findings
The report links AntiFox-hosting infrastructure to IIS web shell activity and authenticated AWS API abuse.
Who said what
We list each claim and who made it. Primary sources (the vendor, the researcher, the registry) are marked. Where reports disagree, we grade by the worst credible case.
- Arctic Wolf Labs original reportPrimaryDocuments observed IIS and AWS activity, scope limits, indicators and containment steps.
- AWS IAM role session revocationPrimaryOfficial procedure to revoke active IAM role sessions.