Rule Category

SERVER-WEBAPP -- Snort has detected traffic exploiting vulnerabilities in web based applications on servers.

Alert Message

SERVER-WEBAPP PHP FPM env_path_info buffer underflow attempt

Rule Explanation

This event is generated when Snort detects an attempt to add or modify PHP configuration via the URL. Impact: Web Application Attack Details: Systems that are configured to run PHP in a potentially unsafe manner could allow an attacker to modify PHP runtime configuration via the URL. An example of this can be found in the proof-of-concept for CVE-2019-11043. Ease of Attack: Simple

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic:

Technique:

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Additional Links

Rule Vulnerability

CVE Additional Information

CVE-2019-11043
In PHP versions 7.1.x below 7.1.33, 7.2.x below 7.2.24 and 7.3.x below 7.3.11 in certain configurations of FPM setup it is possible to cause FPM module to write past allocated buffers into the space reserved for FCGI protocol data, thus opening the possibility of remote code execution.
Details
SeverityHIGH Base Score7.5
Impact Score6.4 Exploit Score10.0
Confidentiality ImpactPARTIAL Integrity ImpactPARTIAL
Availability ImpactPARTIAL Access VectorNETWORK
AuthenticationNONE Ease of AccessLOW