Overview
The cybersecurity world is once again threatened by a newly discovered vulnerability, CVE-2021-42028, that targets the popular application, syngo fastView. This vulnerability affects all versions of the application and opens up a potential pathway for attackers to execute code within the context of the current process, posing a significant risk to system integrity and data security.
Considered a critical flaw with a CVSS severity score of 7.8, it is a matter of urgency for all users of syngo fastView to understand the implications of this vulnerability, the risks it presents, and the steps needed to mitigate its impact. This blog post aims to provide a comprehensive breakdown of this significant cybersecurity issue and provide practical guidance for its mitigation.
Vulnerability Summary
CVE ID: CVE-2021-42028
Severity: Critical (CVSS 7.8)
Attack Vector: Network
Privileges Required: Low
User Interaction: Required
Impact: Potential system compromise or data leakage
Affected Products
No phone number, email, or personal info required.
Product | Affected Versions
syngo fastView | All versions
How the Exploit Works
The vulnerability lies in the way syngo fastView validates user-supplied data when parsing BMP files. An attacker could craft a malicious BMP file that, when processed by the application, causes an out-of-bounds write past the end of an allocated structure.
This condition can lead to a buffer overflow, a classic memory corruption issue, which can be exploited to execute arbitrary code. The code would run in the context of the current process, which could lead to a complete system compromise if the process runs with high privileges.
Conceptual Example Code
While we won’t provide a direct exploit code for ethical and security reasons, we can illustrate the concept with a pseudocode:
# Pseudocode
def exploit(target):
bmp_file = create_malicious_bmp()
send_bmp_to_target(target, bmp_file)
def create_malicious_bmp():
# Create a BMP file with malicious payload which causes buffer overflow
bmp_file = BMPFile()
bmp_file.add_malicious_payload()
return bmp_file
def send_bmp_to_target(target, bmp_file):
# Send the BMP file to the target
target.receive_bmp(bmp_file)In simple terms, the attacker creates a malicious BMP file that causes a buffer overflow when processed by syngo fastView. The attacker then sends this malicious BMP file to the target, which, when opened, executes the malicious payload.
Remember, this is a simplified explanation to help understand the exploit process. Actual exploits could be much more complex and involve advanced techniques to bypass security measures.
Mitigation Guidance
Users are advised to apply the latest patches provided by the vendor. In the absence of a patch, or where patching is not immediately feasible, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) could serve as a temporary mitigation. These tools can help detect and block malicious payloads before they reach the application.