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OSSEC / HIDS Rule 62819

OSSEC / HIDS rule catalog

  • Rule family: OSSEC / HIDS
  • Rule ID: 62819
  • Definition status: Present in current source
  • Alert message / subject: Service Unavailable. The server is currently unable to handle the request due to a temporary overloading or maintenance of the server.
  • Rule level: 5
  • Definition checked: 2026-10-21

Interpretation and response

This event is recorded as “Service Unavailable. The server is currently unable to handle the request due to a temporary overloading or maintenance of the server.” Review the originating log and the affected host or service to determine whether the activity was expected.

An OSSEC/HIDS event records or correlates activity. Blocking depends on the originating application and any separately configured Active Response policy; an alert alone does not prove that an attack was blocked.

Documentation

The following guidance was migrated from the historical wiki and reviewed against the rule definition. Legacy ASL product names and interface instructions refer to the versions documented then. Use the current metadata above and your installed configuration when interpreting thresholds, notification settings and response behavior.

Description

The webserver has returned a 503 error code, which inidcates that the system is currently unable to handle the request due to load, or maintenance.

What you should do

This could be an indicator of an Availability issue due to resource starvation. This could be caused by a DoS attack, or simply because the system is under-resourced. Investigate the system to identify if it was legitimately in a maintenance mode, or if it is otherwise being overloaded.

Troubleshooting

False Positives

A legitimate event may still trigger this rule. Review the surrounding activity before deciding whether it is malicious.

Tuning Guidance

There is no guidance for tuning this rule, this is a generic error and the rule should not be disabled.

Additional Information

Support

If you are unsure about how to respond to this alert, please contact Atomicorp support. We’re here to help you!

Source and revision

Migrated from HIDS_62819, wiki page 848, revision 6213 (20201023). Documentation review: 2026-10-21. An archived wiki status of Active is not a current deployment status.

For assistance, provide the rule ID, installed product and rule version, and a sanitized event to Atomicorp support .