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CVE-2010-1121: Mozilla Firefox: Use after free

CVE-2010-1121 has a CVSS v2 base score of 10.0 (the maximum on that scale) and affects Mozilla Firefox. Per its scoring, it can be exploited over the network, without authentication. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

Mozilla Firefox 3.6.x before 3.6.3 does not properly manage the scopes of DOM nodes that are moved from one document to another, which allows remote attackers to conduct use-after-free attacks and execute arbitrary code via unspecified vectors involving improper interaction with garbage collection, as demonstrated by Nils during a Pwn2Own competition at CanSecWest 2010.

Severity breakdown

CVSS v2.0 10.0: AV:N/AC:L/Au:N/C:C/I:C/A:C

Access vector: Network. Exploitable remotely over the network.
Access complexity: Low. No special conditions are required.
Authentication: None. No authentication is needed.
Confidentiality impact: Complete. Total information disclosure.
Integrity impact: Complete. Total loss of integrity.
Availability impact: Complete. Total shutdown of the component.

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

Mozilla Firefox: 3.6; 3.6.1; 3.6.2