(0Day) Wecon LeviStudioU xmlparser LoadXMLFile XML External Entity Processing Information Disclosure Vulnerability
Vulnerability Details
This vulnerability allows remote attackers to disclose sensitive information on vulnerable installations of Wecon LeviStudioU. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the processing of project files. Due to the improper restriction of XML External Entity (XXE) references, a specially crafted document specifying a URI causes the XML parser to access the URI and embed the contents back into the XML document for further processing. An attacker can leverage this vulnerability to disclose information under the context of Administrator.
Additional Details
Wecon has issued an update to correct this vulnerability. More details can be found at:
https://ics-cert.us-cert.gov/advisories/ICSA-18-212-03
This vulnerability is being disclosed publicly without a patch in accordance with the ZDI 120 day deadline.
05/18/18 - ZDI disclosed the reports to ICS-CERT
07/06/18 - ZDI inquired about the status of the reports
09/19/18 - ZDI notified ICS-CERT of the intent to 0-day these on 9/26
-- Mitigation:
Given the nature of the vulnerability the only salient mitigation strategy is to restrict interaction with the application to trusted files.
Disclosure Timeline
- 2018-05-18 - Vulnerability reported to vendor
- 2018-09-26 - Coordinated public release of advisory
- 2018-09-26 - Advisory Updated
Credit
Jose Luis Zayas Banderas
