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CVE-2018-20768: An issue was discovered on Xerox WorkCentre 3655, 3655i, 58XX, 58XXi, 59XX, 59XXi, 6655, 6655i, 72XX, 72XXi…

CVE-2018-20768 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists 29 affected products, including Xerox Workcentre 3655i Firmware. 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

An issue was discovered on Xerox WorkCentre 3655, 3655i, 58XX, 58XXi, 59XX, 59XXi, 6655, 6655i, 72XX, 72XXi, 78XX, 78XXi, 7970, 7970i, EC7836, and EC7856 devices before R18-05 073.xxx.0487.15000. An attacker can execute PHP code by leveraging a writable file.

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-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

  • Xerox Workcentre 3655i Firmware: before 073.060.048.15000
  • Xerox Workcentre 3655 Firmware: before 073.060.048.15000
  • Xerox Workcentre 5890i Firmware: before 073.190.048.15000
  • Xerox Workcentre 5865i Firmware: before 073.190.048.15000
  • Xerox Workcentre 5875i Firmware: before 073.190.048.15000
  • Xerox Workcentre 5845 Firmware: before 073.190.048.15000
  • Xerox Workcentre 5865 Firmware: before 073.190.048.15000
  • Xerox Workcentre 5875 Firmware: before 073.190.048.15000
  • Xerox Workcentre 5890 Firmware: before 073.190.048.15000
  • Xerox Workcentre 5900 Firmware: before 073.091.048.15000
  • Xerox Workcentre 5900i Firmware: before 073.091.048.15000
  • Xerox Workcentre 6655 Firmware: before 073.110.048.15000
  • Xerox Workcentre 6655i Firmware: before 073.110.048.15000
  • Xerox Workcentre 7855 Firmware: before 073.040.048.15000
  • Xerox Workcentre 7225 Firmware: before 073.030.048.15000

References