Acrobat Reader DC versions 2020.013.20074, 2020.001.30018, and 2017.011.30188 are affected by CVE-2021-21057, allowing denial of service attacks. Learn the impact, technical details, and mitigation steps.
Acrobat Reader DC versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier), and 2017.011.30188 (and earlier) are affected by a null pointer dereference vulnerability, potentially leading to a denial of service attack. Exploiting this vulnerability requires user interaction.
Understanding CVE-2021-21057
This CVE pertains to an invalid memory read in Acrobat Reader DC due to an uninitialized pointer.
What is CVE-2021-21057?
Acrobat Reader DC versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier), and 2017.011.30188 (and earlier) are susceptible to a null pointer dereference vulnerability that could result in denial of service if exploited by an attacker.
The Impact of CVE-2021-21057
The vulnerability could be leveraged by an unauthenticated attacker to cause denial of service in the context of the current user. The exploitation of this issue necessitates user interaction, requiring the victim to open a malicious file.
Technical Details of CVE-2021-21057
The vulnerability is rated with a CVSS v3.1 Base Score of 6.6, indicating a medium severity issue with high availability impact. It has low confidentiality and integrity impacts with no privileges required for exploitation. The attack complexity is low and requires user interaction.
Vulnerability Description
The vulnerability stems from a null pointer dereference (CWE-476) when parsing a specially crafted PDF file, potentially resulting in a denial of service.
Affected Systems and Versions
Acrobat Reader DC versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier), and 2017.011.30188 (and earlier) are impacted by this vulnerability.
Exploitation Mechanism
To exploit this vulnerability, an unauthenticated attacker needs to trick a user into opening a malicious PDF file containing the specially crafted payload.
Mitigation and Prevention
It is crucial to take immediate steps to address CVE-2021-21057 and adopt long-term security practices to prevent such vulnerabilities in the future.
Immediate Steps to Take
Users are advised to update their Acrobat Reader DC to the latest patched version provided by Adobe and refrain from opening PDF files from untrusted or unknown sources.
Long-Term Security Practices
Regularly update applications to patch known vulnerabilities and educate users about safe browsing habits to mitigate the risk of falling victim to such attacks.
Patching and Updates
Adobe has released security updates to address this vulnerability. Users should apply the latest patches promptly to secure their systems.