CVE-2021-28678 : Security Advisory and Response
Learn about the Pillow CVE-2021-28678 vulnerability that allows DoS attacks. Find technical details, impacted systems, and mitigation steps to secure systems against this vulnerability.
An issue was discovered in Pillow before version 8.2.0 that affects BlpImagePlugin, leading to a Denial of Service (DoS) vulnerability where the decoder could run multiple times on empty data. This CVE has been published by MITRE with a detailed description and references.
Understanding CVE-2021-28678
This section will cover the vulnerability description, its impact, technical details, and mitigation steps.
What is CVE-2021-28678?
The vulnerability in Pillow before 8.2.0 allows malicious actors to cause a denial of service condition by exploiting the way BlpImagePlugin handles data, potentially leading to a DoS attack.
The Impact of CVE-2021-28678
The impact of this CVE is significant as it allows attackers to repeatedly run the decoder on empty data, potentially consuming system resources and causing a DoS condition.
Technical Details of CVE-2021-28678
Let's delve deeper into the specific details of the vulnerability, the affected systems and versions, as well as the exploitation mechanism.
Vulnerability Description
The vulnerability arises from the lack of proper checks in the BlpImagePlugin of Pillow before version 8.2.0, enabling attackers to trigger a DoS situation by running the decoder multiple times on empty data.
Affected Systems and Versions
All versions of Pillow prior to 8.2.0 are affected by this vulnerability, making them susceptible to exploitation if not updated to the latest version.
Exploitation Mechanism
By manipulating BLP data, attackers can exploit this vulnerability to repeatedly execute the decoder on empty data, potentially causing resource exhaustion and system unresponsiveness.
Mitigation and Prevention
To safeguard systems from potential exploitation of CVE-2021-28678, immediate steps and long-term security practices should be implemented.
Immediate Steps to Take
It is crucial to update Pillow to version 8.2.0 or later to mitigate the risk of exploitation. Additionally, monitoring for any suspicious behavior can help detect ongoing attacks.
Long-Term Security Practices
Implementing secure coding practices, regular security updates, and threat intelligence sharing can enhance the overall security posture against similar vulnerabilities.
Patching and Updates
Regularly check for security advisories from the vendor and apply patches promptly to address known vulnerabilities and ensure system resilience.