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CVE-2018-1000544: Rubyzip Project: Path traversal

CVE-2018-1000544 is rated critical with a CVSS v3.1 base score of 9.8 and affects Rubyzip Project, along with 2 other products 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

rubyzip gem rubyzip version 1.2.1 and earlier contains a Directory Traversal vulnerability in Zip::File component that can result in write arbitrary files to the filesystem. This attack appear to be exploitable via If a site allows uploading of .zip files , an attacker can upload a malicious file that contains symlinks or files with absolute pathnames "../" to write arbitrary files to the filesystem..

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-59: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

CWE-434: Unrestricted Upload of File with Dangerous Type

The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.

Affected products

  • Rubyzip Project: up to and including 1.2.1
  • Debian Linux: 8.0; 9.0
  • Red Hat Cloudforms: 4.6

References