Rule Document 1:59928

Rule Category

MALWARE-BACKDOOR -- Snort has detected suspicious communication traffic unrelated to commands, such as exfiltration of data from the infected machine, especially larger chunks of data.

Alert Message

MALWARE-BACKDOOR Jsp.Webshell.Chopper webshell download attempt

Rule Explanation

This rule looks for a Chopper webshell that is downloaded to a server. This would likely occur during or after exploitation.

What To Look For

This rule is caused by an download attempt of the Chopper webshell.

Known Usage

Attacks/Scans seen in the wild

False Positives

Known false positives, with the described conditions

This could occur from benign Java code being uploaded to a webserver.

Contributors

Cisco Talos Intelligence Group

Rule Groups

No rule groups

CVE

CVE-2022-26134

Additional Links

community.atlassian.com/t5/Confluence-discussions/CVE-2022-26134-Critical-severity-unauthenticated-remote-code/td-p/20456533

Rule Vulnerability

Remote File Inclusion

Remote File Inclusion (RFI) attacks occur when a webserver takes a file crafted by an attacker as input and runs or stores it in an unsafe manner. For instance, the webserver could accept an image file that is actually code, then call it to execute after uploading. RFI attacks happen on web applications that dynamically include external files or scripts. A successful RFI can lead to data leaks, remote code execution, or cross site scripting. Avoid dynamic inclusion of user input files, or whitelist files that may be included. Keep the PHP allow_url_include option set to off; this will not protect against Local File Inclusion attacks.

CVE Additional Information

This product uses data from the NVD API but is not endorsed or certified by the NVD.

CVE-2022-26134

Loading description

MITRE ATT&CK Framework

Tactic: Command and Control

Technique: Custom Command and Control Protocol

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