CVE Vulnerabilities

CVE-2012-1521

Use After Free

Published: May 01, 2012 | Modified: Apr 13, 2020
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
3.7 MODERATE
AV:L/AC:H/Au:N/C:P/I:P/A:P
RedHat/V3
Ubuntu

Use-after-free vulnerability in the XML parser in Google Chrome before 18.0.1025.168 allows remote attackers to cause a denial of service or possibly have unspecified other impact via unknown vectors.

Weakness

Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

Affected Software

Name Vendor Start Version End Version
Chrome Google * *
Chromium-browser Ubuntu lucid *
Chromium-browser Ubuntu natty *
Chromium-browser Ubuntu oneiric *
Chromium-browser Ubuntu precise *
Chromium-browser Ubuntu quantal *
Chromium-browser Ubuntu upstream *
Webkit Ubuntu hardy *
Webkit Ubuntu lucid *
Webkit Ubuntu natty *
Webkit Ubuntu oneiric *
Webkit Ubuntu precise *
Webkit Ubuntu upstream *

Extended Description

The use of previously-freed memory can have any number of adverse consequences, ranging from the corruption of valid data to the execution of arbitrary code, depending on the instantiation and timing of the flaw. The simplest way data corruption may occur involves the system’s reuse of the freed memory. Use-after-free errors have two common and sometimes overlapping causes:

In this scenario, the memory in question is allocated to another pointer validly at some point after it has been freed. The original pointer to the freed memory is used again and points to somewhere within the new allocation. As the data is changed, it corrupts the validly used memory; this induces undefined behavior in the process. If the newly allocated data chances to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Potential Mitigations

References