CVE-2021-45465: Critical BMP Parsing Vulnerability in syngo fastView

Overview

The Common Vulnerabilities and Exposures (CVE) system has identified a significant vulnerability in all versions of syngo fastView, a software widely used in the healthcare sector for viewing and interpreting medical images. The vulnerability is identified by the CVE ID: CVE-2021-45465. The severity of this vulnerability is heightened given that it has the potential to compromise system integrity or lead to data leakage, impacting not just the operation of healthcare services but also the privacy of patient data. Therefore, understanding and addressing this vulnerability is of paramount importance.

Vulnerability Summary

CVE ID: CVE-2021-45465
Severity: High (CVSS: 7.8)
Attack Vector: Local
Privileges Required: Low
User Interaction: Required
Impact: System Compromise, Potential Data Leakage

Affected Products

Product | Affected Versions

syngo fastView | All versions

How the Exploit Works

The vulnerability in syngo fastView arises due to inadequate validation of user-supplied data when parsing BMP files. This leads to a write-what-where condition, which means that an attacker can write data to any location they choose. By exploiting this vulnerability, an attacker is able to execute arbitrary code within the context of the current process.

Conceptual Example Code

The vulnerability could be exploited by an attacker sending a malicious BMP file to the victim. The file, when opened in syngo fastView, would execute the attacker’s code. The example below is a conceptual representation of the malicious BMP file.

# Create a malicious .bmp file
echo -e '\x42\x4d\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c\x4c' > malicious.bmp
# The sequence above represents the BMP header followed by the malicious code.

It’s important to note that the actual exploitation of this vulnerability would require a more complex sequence of commands and likely involve obfuscation techniques to avoid detection.

Countermeasures

To mitigate the risks associated with CVE-2021-45465, users are advised to apply a vendor-supplied patch. If a patch is not immediately available or can’t be installed promptly, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) may provide temporary mitigation. These measures can help identify and block attempts to exploit the vulnerability. However, they are not a permanent solution and applying the official patch should be a priority to ensure robust protection.