Rapid7 Vulnerability & Exploit Database

MFSA2021-10 Firefox: Security Vulnerabilities fixed in Firefox 87 (CVE-2021-23986)

Free InsightVM Trial No Credit Card Necessary
2024 Attack Intel Report Latest research by Rapid7 Labs
Gartner Peer insights
4.4 Gartner Rating
Back to Search

MFSA2021-10 Firefox: Security Vulnerabilities fixed in Firefox 87 (CVE-2021-23986)

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:N)
Published
03/23/2021
Created
03/24/2021
Added
03/24/2021
Modified
04/07/2021

Description

A malicious extension with the 'search' permission could have installed a new search engine whose favicon referenced a cross-origin URL. The response to this cross-origin request could have been read by the extension, allowing a same-origin policy bypass by the extension, which should not have cross-origin permissions. This cross-origin request was made without cookies, so the sensitive information disclosed by the violation was limited to local-network resources or resources that perform IP-based authentication. This vulnerability affects Firefox < 87.

Solution(s)

  • mozilla-firefox-upgrade-87_0

insightVM

Advanced vulnerability management analytics and reporting.
Key Features
  • Lightweight Endpoint Agent
  • Live Dashboards
  • Real Risk Prioritization
  • IT-Integrated Remediation Projects
  • Cloud, Virtual, and Container Assessment
  • Integrated Threat Feeds
  • Easy-to-Use RESTful API
  • Automation-Assisted Patching
  • Automated Containment
Free InsightVM Trial WATCH DEMO

With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.

– Scott Cheney, Manager of Information Security, Sierra View Medical Center

;