In the module “Custom Exporter” (customexporter) from Webbax for PrestaShop, a guest can download personal information without restriction by performing a path traversal attack.

Summary

  • CVE ID: CVE-2023-30199
  • Published at: 2023-05-16
  • Platform: PrestaShop
  • Product: customexporter
  • Impacted release: <= 1.7.20 (1.7.21 fixed the vulnerability)
  • Product author: Webbax
  • Weakness: CWE-22
  • Severity: high (7.5), GDPR violation

Description

Due to a lack of permissions control and a lack of control in the path name construction, a guest can perform a path traversal to view all files on the information system.

Note : We are forced to tag it as a high gravity due to the CWE type 22 but be warned that on our ecosystem, it must be considered critical since it unlocks hundreds admin’s ajax script of modules due to this

WARNING : Be informed that this vulnerability is exploited since March 30, 2023.

CVSS base metrics

  • Attack vector: network
  • Attack complexity: low
  • Privilege required: none
  • User interaction: none
  • Scope: unchanged
  • Confidentiality: high
  • Integrity: none
  • Availability: none

Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Possible malicious usage

  • Stealing secrets to unlock admin controllers based on ajax script
  • Exfiltrate all modules with all versions to facilitate pentesting
  • Stealing table_prefix to greatly facilitate SQL injections for kiddies who don’t know how to exploit DBMS design’s vulnerabilities or steal database access to login in exposed PHPMyAdmin/Adminer/etc.
  • Bypass WAF / htaccess restrictions to read forbidden files (such as logs on predictable paths of banks’s modules inside /var/log/)

Patch from 1.7.20

--- 1.7.20/modules/customexporter/downloads/download.php
+++ 1.7.21/modules/customexporter/downloads/download.php
...
- $file = Tools::getValue('file');
+ $file = basename(Tools::getValue('file'));

if(strpos($file,'?')!==false){
   $file_name = explode('?',$file);
   $file = str_replace('file=','',$file_name[0]);
}

-
+if((strpos($file, './') === false) && (substr($file,-4) === '.csv') || substr($file,-4) === '.txt'){
...
-
+}

Other recommendations

  • It’s recommended to upgrade to the latest version of the module customexporter.
  • You should consider restricting the access of modules/customexporter/ to a whitelist
  • NEVER expose a PHPMyAdmin / Adminer / etc without, at least, a htpasswd
  • Activate OWASP 930’s rules on your WAF (Web application firewall) and adjust it for your PrestaShop

Timeline

Date Action
2023-02-25 Issue discovered during a code review by TouchWeb.fr
2023-02-25 Contact Author
2023-02-25 Request a CVE ID
2023-02-27 Author confirms alert’s read
2023-04-24 Received CVE ID
2023-05-02 Author publishes a new version which fix the leak
2023-05-16 Publish this security advisory