Quantum Secular Labs / Blog / Advisories

CVE-2018-11788: Apache Karaf: XML external entity injection

CVE-2018-11788 is rated critical with a CVSS v3.0 base score of 9.8 and affects Apache Karaf. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

Apache Karaf provides a features deployer, which allows users to "hot deploy" a features XML by dropping the file directly in the deploy folder. The features XML is parsed by XMLInputFactory class. Apache Karaf XMLInputFactory class doesn't contain any mitigation codes against XXE. This is a potential security risk as an user can inject external XML entities in Apache Karaf version prior to 4.1.7 or 4.2.2. It has been fixed in Apache Karaf 4.1.7 and 4.2.2 releases.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-611: Improper Restriction of XML External Entity Reference

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 products

  • Apache Karaf: before 4.1.7; from 4.2.0 up to and including 4.2.1; 4.2.0 milestone1; 4.2.0 milestone2

References