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CVE-2017-6094: Genexis Gaps: Exposure of Sensitive Information to an Unauthorized Actor

CVE-2017-6094 is rated critical with a CVSS v3.0 base score of 9.8 and affects Genexis Gaps. 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

CPEs used by subscribers on the access network receive their individual configuration settings from a central GAPS instance. A CPE identifies itself by the MAC address of its WAN interface and a certain "chk" value (48bit) derived from the MAC. The algorithm used to compute the "chk" was disclosed by reverse engineering the CPE's firmware. As a result, it is possible to forge valid "chk" values for any given MAC address and therefore receive the configuration settings of other subscribers' CPEs. The configuration settings often contain sensitive values, for example credentials (username/password) for VoIP services. This issue affects Genexis B.V. GAPS up to 7.2.

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-200: Exposure of Sensitive Information to an Unauthorized Actor

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Affected products

  • Genexis Gaps: before 7.2

References