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CVE-2017-14100: Digium Asterisk: Command injection

CVE-2017-14100 is rated critical with a CVSS v3.0 base score of 9.8 and affects Digium Asterisk. 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

In Asterisk 11.x before 11.25.2, 13.x before 13.17.1, and 14.x before 14.6.1 and Certified Asterisk 11.x before 11.6-cert17 and 13.x before 13.13-cert5, unauthorized command execution is possible. The app_minivm module has an "externnotify" program configuration option that is executed by the MinivmNotify dialplan application. The application uses the caller-id name and number as part of a built string passed to the OS shell for interpretation and execution. Since the caller-id name and number can come from an untrusted source, a crafted caller-id name or number allows an arbitrary shell command injection.

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-78: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

Affected products

  • Digium Asterisk: 13.0.0; 13.0.0 beta1; 13.0.0 beta2; 13.0.0 beta3; 13.0.1; 13.0.2; 13.1.0; 13.1.0 rc1; 13.1.0 rc2; 13.1.1; 13.2.0; 13.2.0 rc1
  • Digium Certified Asterisk: 11.6 cert1; 11.6 cert1_rc1; 11.6 cert1_rc2; 11.6 cert10; 11.6 cert11; 11.6 cert12; 11.6 cert13; 11.6 cert14; 11.6 cert14_rc1; 11.6 cert14_rc2; 11.6 cert15; 11.6 cert16

References