CVE Vulnerabilities


Use After Free

Published: Mar 02, 2023 | Modified: Nov 07, 2023
CVSS 3.x
CVSS 2.x

A use-after-free vulnerability in WebCore::RenderLayer::addChild in WebKitGTK before 2.36.8 allows attackers to execute code remotely.


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
Webkitgtk Webkitgtk * 2.36.8 (excluding)
Red Hat Enterprise Linux 8 RedHat webkit2gtk3-0:2.38.5-1.el8 *
Red Hat Enterprise Linux 9 RedHat webkit2gtk3-0:2.38.5-1.el9 *
Qtwebkit-opensource-src Ubuntu bionic *
Qtwebkit-opensource-src Ubuntu kinetic *
Qtwebkit-opensource-src Ubuntu lunar *
Qtwebkit-opensource-src Ubuntu trusty *
Qtwebkit-opensource-src Ubuntu xenial *
Qtwebkit-source Ubuntu bionic *
Qtwebkit-source Ubuntu trusty *
Qtwebkit-source Ubuntu xenial *
Webkit2gtk Ubuntu bionic *
Webkit2gtk Ubuntu focal *
Webkit2gtk Ubuntu jammy *
Webkit2gtk Ubuntu kinetic *
Webkit2gtk Ubuntu xenial *
Webkitgtk Ubuntu bionic *
Webkitgtk Ubuntu trusty *
Webkitgtk Ubuntu xenial *
Wpewebkit Ubuntu trusty *

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 happens 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