> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/analytics-alerts/alerts-by-name/suspicious-failed-http-request-potential-spring4shell-exploit.md).

# Suspicious failed HTTP request - potential Spring4Shell exploit

### Synopsis

| Field                | Value                                                                                                   |
| -------------------- | ------------------------------------------------------------------------------------------------------- |
| Activation Period    | 14 Days                                                                                                 |
| Training Period      | 30 Days                                                                                                 |
| Test Period          | N/A (single event)                                                                                      |
| Deduplication Period | 1 Day                                                                                                   |
| Required Data        | <p>Requires one of the following data sources:<br>Palo Alto Networks Firewall EAL Logs OR XDR Agent</p> |
| ATT\&CK Tactic       | Initial Access (TA0001)                                                                                 |
| ATT\&CK Technique    | Exploit Public-Facing Application (T1190)                                                               |
| Severity             | Low                                                                                                     |

### Description

A potentially malicious failed HTTP request was received, possibly as part of a Spring4Shell exploitation attempt.

### Attacker's Goals

Gain the ability to execute code remotely or drop malware.

### Investigative actions

* Check if suspicious process executions occurred after the request.
* Consider limiting access to the vulnerable server.

### Variations

<details>

<summary>Suspicious HTTP request - potential Spring4Shell exploit</summary>

**Synopsis**

| Field             | Value                                     |
| ----------------- | ----------------------------------------- |
| ATT\&CK Tactic    | Initial Access (TA0001)                   |
| ATT\&CK Technique | Exploit Public-Facing Application (T1190) |
| Severity          | Medium                                    |

**Description**

A potentially malicious HTTP request was received, possibly as part of a Spring4Shell exploitation attempt.

**Attacker's Goals**

Gain the ability to execute code remotely or drop malware.

**Investigative actions**

* Check if suspicious process executions occurred after the request.
* Consider limiting access to the vulnerable server.

</details>


---

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