Microsoft Edge Could Allow for Arbitrary Code Execution

Fortify Security Team
Sep 28, 2021

Multiple vulnerabilities have been discovered in Microsoft Edge, the most severe of which could result in remote code execution. Microsoft Edge is a Chromium based internet browser made by Microsoft, which is installed by default on all new Windows computers. Edge was made to replace Internet Explorer, and runs faster and with more features. Successful exploitation of the most severe of these vulnerabilities could allow an attacker to execute arbitrary code in the context of the browser. Depending on the privileges associated with the application, an attacker could view, change, or delete data. If this application has been configured to have fewer user rights on the system, exploitation of the most severe of these vulnerabilities could have less impact than if it was configured with administrative rights.

THREAT INTELLIGENCE: According to Google, an exploit for CVE-2021-37973 exists in the wild.

SYSTEMS AFFECTED:

  • Microsoft Edge (Chromium-based) prior to 94.0.992.31

RISK:

Government:

  • Large and medium government entities: High
  • Small government: Medium

Businesses:

  • Large and medium business entities: High
  • Small business entities: Medium

Home users: Low

TECHNICAL SUMMARY:

Multiple vulnerabilities have been discovered in Microsoft Edge (Chromium Based), the most severe of which could allow for arbitrary code execution. Details of the vulnerabilities are as follows:

  • Use after free vulnerability exists in Offline use. (CVE-2021-37956)
  • Use after free vulnerability exists in WebGPU. (CVE-2021-37957)
  • Inappropriate implementation vulnerability exists in Navigation. (CVE-2021-37958)
  • Use after free vulnerability exists in Task Manager. (CVE-2021-37959)
  • Inappropriate implementation vulnerability exists in Blink graphics. (CVE-2021-37960)
  • Use after free vulnerability exists in Tab Strip. (CVE-2021-37961)
  • Use after free vulnerability exists in Performance Manager. (CVE-2021-37962)
  • Side-channel information leakage vulnerability exists in DevTools. (CVE-2021-37963)
  • Inappropriate implementation vulnerability exists in ChromeOS Networking. (CVE-2021-37964)
  • Inappropriate implementation vulnerability exists in Background Fetch API. (CVE-2021-37965)
  • Inappropriate implementation vulnerability exists in Compositing. (CVE-2021-37966)
  • Inappropriate implementation vulnerability exists in Background Fetch API. (CVE-2021-37967)
  • Inappropriate implementation vulnerability exists in Background Fetch API. (CVE-2021-37968)
  • Inappropriate implementation vulnerability exists in Google Updater. (CVE-2021-37969)
  • Use after free vulnerability exists in File System API. (CVE-2021-37970)
  • Incorrect security UI vulnerability exists in Web Browser UI. (CVE-2021-37971)
  • Out of bounds read vulnerability exists in libjpeg-turbo. (CVE-2021-37972)
  • Use after free vulnerability exists in Portals. (CVE-2021-37973)

Successful exploitation of the most severe of these vulnerabilities could allow an attacker to execute arbitrary code in the context of the browser. Depending on the privileges associated with the application, an attacker could view, change, or delete data. If this application has been configured to have fewer user rights on the system, exploitation of the most severe of these vulnerabilities could have less impact than if it was configured with administrative rights.

RECOMMENDATIONS:

We recommend the following actions be taken:

  • Apply the security updates provided by Microsoft to vulnerable systems immediately after appropriate testing.
  • Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from un-trusted sources.
  • Apply the Principle of Least Privilege to all systems and services.

REFERENCES:

Microsoft:

https://msrc.microsoft.com/update-guide/

CVE:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37956

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37957

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37958

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37959

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37960

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37961

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37962

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37963

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37964

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37965

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37966

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37967

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37968

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37969

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37970

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37971

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37972

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37973

Recent Posts

Mozilla Products Could Allow for Arbitrary Code Execution

Multiple vulnerabilities have been discovered in Mozilla Firefox and Mozilla Thunderbird, the most severe of which could allow for arbitrary code execution. Mozilla Firefox is a web browser used to access the Internet. Mozilla Firefox ESR is a version of the web...

Apple Products Could Allow for Arbitrary Code Execution

Multiple vulnerabilities have been discovered in Apple Products, the most severe of which could allow for arbitrary code execution. macOS Ventura is the 19th and current major release of macOS iOS is a mobile operating system for mobile devices, including the iPhone,...

Citrix ADC and Gateway Could Allow for Authentication Bypass

Multiple vulnerabilities have been discovered in Citrix ADC and Gateway, the most severe of which could allow for Authentication Bypass. Citrix ADC and Gateway is an Application Delivery Controller and a gateway service to products respectively. Successful...