CVE Vulnerabilities

CVE-2023-21808

Use After Free

Published: Feb 14, 2023 | Modified: Nov 21, 2024
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
RedHat/V2
RedHat/V3
7.8 IMPORTANT
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM

.NET and Visual Studio Remote Code Execution Vulnerability

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
.net Microsoft 6.0.0 (including) 6.0.0 (including)
.net Microsoft 7.0.0 (including) 7.0.0 (including)
Visual_studio_2017 Microsoft 15.0 (including) 15.9.51 (excluding)
Visual_studio_2019 Microsoft 16.0 (including) 16.11.24 (excluding)
Visual_studio_2022 Microsoft 17.0 (including) 17.0 (including)
Visual_studio_2022 Microsoft 17.2 (including) 17.2 (including)
Visual_studio_2022 Microsoft 17.4 (including) 17.4 (including)
Dotnet6 Ubuntu upstream *
Dotnet7 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 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

References