CVE-2021-23986 Explained : Impact and Mitigation
Discover how the CVE-2021-23986 vulnerability in Firefox < 87 allowed malicious extensions to bypass the same-origin policy, potentially exposing sensitive data.
A malicious extension in Firefox prior to version 87 with 'search' permission could have bypassed the same-origin policy, potentially disclosing sensitive information from cross-origin requests.
Understanding CVE-2021-23986
This vulnerability allowed a malicious extension in Firefox to violate the same-origin policy, leading to a potential security compromise.
What is CVE-2021-23986?
The CVE-2021-23986 vulnerability pertains to Firefox versions before 87, where a malicious extension with specific permissions could have exploited a flaw to access cross-origin responses.
The Impact of CVE-2021-23986
The impact of this vulnerability could have resulted in unauthorized access to sensitive information via same-origin policy bypasses, affecting local-network or IP-based authentication systems.
Technical Details of CVE-2021-23986
This section delves into the technical aspects of the CVE, providing insights into the vulnerability, affected systems, and exploitation mechanisms.
Vulnerability Description
A malicious extension with the 'search' permission could leverage a flaw to read responses from cross-origin requests, bypassing the same-origin policy.
Affected Systems and Versions
The vulnerability affects Firefox versions earlier than 87, providing an opportunity for exploitation by extensions with the 'search' permission.
Exploitation Mechanism
By installing a search engine with a cross-origin URL favicon, the extension could trigger a same-origin policy bypass, potentially accessing cross-origin responses.
Mitigation and Prevention
This section offers guidance on immediate steps to mitigate the risks and prevent such vulnerabilities in the long term.
Immediate Steps to Take
Users are advised to update Firefox to version 87 or later to mitigate the CVE-2021-23986 vulnerability and enhance security.
Long-Term Security Practices
Maintaining updated browser versions, avoiding untrusted extensions, and monitoring permissions can help in preventing similar vulnerabilities.
Patching and Updates
Regularly applying security patches and updates provided by Mozilla can address known vulnerabilities and enhance browser security.