Quantum Secular Labs / Blog / Advisories

CVE-2017-3206: Exadel Flamingo: Insecure deserialization

CVE-2017-3206 is rated critical with a CVSS v3.0 base score of 9.8 and affects Exadel Flamingo. 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

The Java implementation of AMF3 deserializers used by Flamingo amf-serializer by Exadel, version 2.2.0, allows external entity references (XXEs) from XML documents embedded within AMF3 messages. If the XML parsing is handled incorrectly it could potentially expose sensitive data on the server, denial of service, or server side request forgery.

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

  • Exadel Flamingo: 2.2.0

References