Quantum Secular Labs / Blog / Advisories

CVE-2018-7739: Antsle Antman: Authentication bypass

CVE-2018-7739 is rated critical with a CVSS v3.0 base score of 9.8 and affects Antsle Antman. 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

antsle antman before 0.9.1a allows remote attackers to bypass authentication via invalid characters in the username and password parameters, as demonstrated by a username=>&password=%0a string to the /login URI. This allows obtaining root permissions within the web management console, because the login process uses Java's ProcessBuilder class and a bash script called antsle-auth with insufficient input validation.

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-20: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

Affected products

  • Antsle Antman: up to and including 0.9.0c

References