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CVE-2016-4448: Xmlsoft Libxml2: Use of Externally-Controlled Format String

CVE-2016-4448 is rated critical with a CVSS v3.1 base score of 9.8 and affects Xmlsoft Libxml2, along with 18 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

Format string vulnerability in libxml2 before 2.9.4 allows attackers to have unspecified impact via format string specifiers in unknown vectors.

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-134: Use of Externally-Controlled Format String

The product uses a function that accepts a format string as an argument, but the format string originates from an external source.

Affected products

  • Xmlsoft Libxml2: up to and including 2.9.3
  • HP Icewall Federation Agent: 3.0
  • Apple Watchos: up to and including 2.2.1
  • Apple Mac OS X: before 10.11.6
  • Apple Icloud: before 5.2.1
  • Apple Iphone OS: up to and including 9.3.2
  • Red Hat Enterprise Linux Desktop: 6.0; 7.0
  • Red Hat Enterprise Linux Server: 6.0; 7.0
  • Red Hat Enterprise Linux Server Aus: 7.2; 7.3; 7.4; 7.6; 7.7
  • Red Hat Enterprise Linux Server Eus: 7.2; 7.3; 7.4; 7.5; 7.6; 7.7
  • Red Hat Enterprise Linux Server Tus: 7.2; 7.3; 7.6; 7.7
  • Red Hat Enterprise Linux Workstation: 6.0; 7.0
  • Apple Itunes: up to and including 12.4.1
  • Slackware Linux: 14.0; 14.1
  • Oracle Vm Server: 3.3; 3.4

References