Vulnerabilities > CVE-2020-15103 - Integer Overflow to Buffer Overflow vulnerability in multiple products

In FreeRDP less than or equal to 2.1.2, an integer overflow exists due to missing input sanitation in rdpegfx channel. All FreeRDP clients are affected. The input rectangles from the server are not checked against local surface coordinates and blindly accepted. A malicious server can send data that will crash the client later on (invalid length arguments to a `memcpy`) This has been fixed in 2.2.0. As a workaround, stop using command line arguments /gfx, /gfx-h264 and /network:auto

Vulnerable Configurations

Part	Description	Count
Application	Freerdp Freerdp Freerdp - Freerdp Freerdp 1.0.0 Freerdp Freerdp 1.0.1 Freerdp Freerdp 1.0.2 Freerdp Freerdp 1.1.0 Freerdp Freerdp 1.2.0 Freerdp Freerdp 2.0.0 Freerdp Freerdp 2.1.0 Freerdp Freerdp 2.1.1 Freerdp Freerdp 2.1.2	27
OS	Fedoraproject Fedoraproject Fedora 31 Fedoraproject Fedora 32	2
OS	Opensuse Opensuse Leap 15.1	1
OS	Canonical Canonical Ubuntu Linux 20.04 Canonical Ubuntu Linux 18.04	2
OS	Debian Debian Debian Linux 10.0	1

Common Weakness Enumeration (CWE)

CWE-680 - Integer Overflow to Buffer Overflow

Common Attack Pattern Enumeration and Classification (CAPEC)

Buffer Overflow via Environment Variables
This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
Overflow Buffers
Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
Client-side Injection-induced Buffer Overflow
This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
Filter Failure through Buffer Overflow
In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
Buffer Overflow via Symbolic Links
This type of attack leverages the use of symbolic links to cause buffer overflows. An attacker can try to create or manipulate a symbolic link file such that its contents result in out of bounds data. When the target software processes the symbolic link file, it could potentially overflow internal buffers with insufficient bounds checking.

Summary

Vulnerable Configurations

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

References