Suspicious User and Network Namespace Creation via unshare on Linux

PremiumReviewedSigma · Medium · v1
Product
linux
Category
process_creation
Author
HuntRule
Published
2026-05-22
Updated
2026-08-28

ATT&CK techniques

Priv Esc → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule detects use of unshare to create combined user and network namespaces as leveraged by the Copy Fail and DirtyFrag Linux page cache exploits in Elastic research. Unprivileged user namespace creation is a common precursor to kernel exploitation that grants capabilities inside the new namespace for privilege escalation.

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Suspicious User and Network Namespace Creation via unshare on Linux
Pivot detection · T1068 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.