Quantum Secular Labs / Blog / Advisories

CVE-2018-18504: Mozilla Firefox: Memory corruption

CVE-2018-18504 is rated critical with a CVSS v3.0 base score of 9.8 and affects Mozilla Firefox, along with 1 other product in NVD’s configuration data. 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

A crash and out-of-bounds read can occur when the buffer of a texture client is freed while it is still in use during graphic operations. This results is a potentially exploitable crash and the possibility of reading from the memory of the freed buffers. This vulnerability affects Firefox < 65.

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-125: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

Affected products

  • Mozilla Firefox: before 65.0
  • Canonical Ubuntu Linux: 14.04; 16.04; 18.04; 18.10

References