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CVE-2018-1999019: Chamilo Lms: Authentication bypass

CVE-2018-1999019 is rated critical with a CVSS v3.1 base score of 9.8 and affects Chamilo Lms. 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

Chamilo LMS version 11.x contains an Unserialization vulnerability in the "hash" GET parameter for the api endpoint located at /webservices/api/v2.php that can result in Unauthenticated remote code execution. This attack appear to be exploitable via a simple GET request to the api endpoint. This vulnerability appears to have been fixed in After commit 0de84700648f098c1fbf6b807dee28ec640efe62.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/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-94: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

Affected products

  • Chamilo Lms: 1.11.0; 1.11.0 alpha2; 1.11.0 beta1; 1.11.0 beta2; 1.11.0 beta3; 1.11.0 beta4; 1.11.0 beta5; 1.11.0 beta6; 1.11.0 beta7; 1.11.0 rc1; 1.11.2; 1.11.4

References