Techniques › T1499.002 › AN0490
AN0490 Analytic 0490
Linux · attack.mitre.org · ATT&CK Enterprise v19.2
<p>Excessive inbound HTTP or TLS connections to services such as Apache or Nginx, causing worker thread exhaustion or segmentation faults.</p>
- Detects
- T1499.002 Service Exhaustion Flood
- Part of
- DET0173 Detection Strategy for Endpoint DoS via Service Exhaustion Flood
Log sources and channels
Exactly as MITRE states them in x_mitre_log_source_references. Where a channel is vague, it is vague in the source; kevmap does not tidy it.
| Log source | Channel | Data component |
|---|---|---|
| auditd:SYSCALL | High frequency of accept(), read(), or SSL_read() syscalls tied to nginx/apache processes | DC0035 Process Access |
| NSM:Flow | Sudden spike in incoming flows to web service ports from single/multiple IPs | DC0078 Network Traffic Flow |
| linux:syslog | Repetitive HTTP 408, 500, or 503 errors logged within short timeframe | DC0038 Application Log Content |
Mutable elements
Parameters MITRE marks as environment-specific. These are the knobs you are expected to tune; they are why an analytic is not a rule.
| Field | Description |
|---|---|
ErrorCodeWindow | Tunable count of specific HTTP error codes in timeframe |
ConnectionRateThreshold | Defines number of connections per second considered anomalous |
KEV CVEs whose mapped technique this analytic detects
| CVE | Vendor / product | State |
|---|---|---|
| CVE-2021-45382 | D-Link Multiple Routers | Mapped |
| CVE-2022-26258 | D-Link DIR-820L | Mapped |