CVE Vulnerabilities

CVE-2022-1700

Improper Restriction of XML External Entity Reference

Published: Sep 12, 2022 | Modified: Sep 15, 2022
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

Improper Restriction of XML External Entity Reference (XXE) vulnerability in the Policy Engine of Forcepoint Data Loss Prevention (DLP), which is also leveraged by Forcepoint One Endpoint (F1E), Web Security Content Gateway, Email Security with DLP enabled, and Cloud Security Gateway prior to June 20, 2022. The XML parser in the Policy Engine was found to be improperly configured to support external entities and external DTD (Document Type Definitions), which can lead to an XXE attack. This issue affects: Forcepoint Data Loss Prevention (DLP) versions prior to 8.8.2. Forcepoint One Endpoint (F1E) with Policy Engine versions prior to 8.8.2. Forcepoint Web Security Content Gateway versions prior to 8.5.5. Forcepoint Email Security with DLP enabled versions prior to 8.5.5. Forcepoint Cloud Security Gateway prior to June 20, 2022.

Weakness

The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

Affected Software

Name Vendor Start Version End Version
Cloud_security_gateway Forcepoint * 2022-06-20 (excluding)
Data_loss_prevention Forcepoint * 8.8.2 (excluding)
Email_security Forcepoint * 8.5.5 (excluding)
One_endpoint_with_policy_engine Forcepoint * 8.8.2 (excluding)
Web_security_content_gateway Forcepoint * 8.5.5 (excluding)

Extended Description

XML documents optionally contain a Document Type Definition (DTD), which, among other features, enables the definition of XML entities. It is possible to define an entity by providing a substitution string in the form of a URI. The XML parser can access the contents of this URI and embed these contents back into the XML document for further processing. By submitting an XML file that defines an external entity with a file:// URI, an attacker can cause the processing application to read the contents of a local file. For example, a URI such as “file:///c:/winnt/win.ini” designates (in Windows) the file C:\Winnt\win.ini, or file:///etc/passwd designates the password file in Unix-based systems. Using URIs with other schemes such as http://, the attacker can force the application to make outgoing requests to servers that the attacker cannot reach directly, which can be used to bypass firewall restrictions or hide the source of attacks such as port scanning. Once the content of the URI is read, it is fed back into the application that is processing the XML. This application may echo back the data (e.g. in an error message), thereby exposing the file contents.

Potential Mitigations

References