Spike in Firewall Denies
A machine learning job detected an unusually large spike in network traffic that was denied by network access control lists (ACLs) or firewall rules. Such a burst of denied traffic is usually caused by either 1) a…
Description
A machine learning job detected an unusually large spike in network traffic that was denied by network access control lists (ACLs) or firewall rules. Such a burst of denied traffic is usually caused by either 1) a mis-configured application or firewall or 2) suspicious or malicious activity. Unsuccessful attempts at network transit, in order to connect to command-and-control (C2), or engage in data exfiltration, may produce a burst of failed connections. This could also be due to unusually large amounts of reconnaissance or enumeration traffic. Denial-of-service attacks or traffic floods may also produce such a surge in traffic.
Detection logic
Its licence does not clear it for publishing here
Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.
Detection requirements
- Platform
- ContainersESXiIaaSLinuxmacOSNetwork DevicesPREWindows
The rule states no platform. This is derived from the 8 ATT&CK techniques it maps to.
Known benign triggers
- A misconfgured network application or firewall may trigger this alert. Security scans or test cycles may trigger this alert.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| www.elastic.co/guide/en/security/current/prebuilt-ml-jobs.html | 103 |
From the source
- At source
- Open at source
- Upstream identifier
- eaa77d63-9679-4ce3-be25-3ba8b795e5fa
- Tagged by the source as
- Data Source: Elastic DefendData Source: Network Packet CaptureDomain: EndpointDomain: NetworkResources: Investigation GuideRule Type: Machine LearningRule Type: MLUse Case: Threat Detection
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 20, 2026
- Version
- 2