Security Advisory for Flash Player | APSA18-01
Bulletin ID Date Published Priority
APSA18-01 February 1, 2018 1

Summary

A critical vulnerability (CVE-2018-4878) exists in Adobe Flash Player 28.0.0.137 and earlier versions. Successful exploitation could potentially allow an attacker to take control of the affected system.

Adobe is aware of a report that an exploit for CVE-2018-4878 exists in the wild, and is being used in limited, targeted attacks against Windows users. These attacks leverage Office documents with embedded malicious Flash content distributed via email.

Adobe addressed this vulnerability in version 28.0.0.161, released on February 6, 2018.  See this bulletin for more details.  

Note:

The ActiveX component used in Adobe Connect is not impacted by CVE-2018-4878.

Affected Product Versions

Product Version Platform
Adobe Flash Player Desktop Runtime 28.0.0.137 and earlier versions Windows, Macintosh
Adobe Flash Player for Google Chrome 28.0.0.137 and earlier versions Windows, Macintosh, Linux and Chrome OS 
Adobe Flash Player for Microsoft Edge and Internet Explorer 11 28.0.0.137 and earlier versions Windows 10 and 8.1
Adobe Flash Player Desktop Runtime 28.0.0.137 and earlier versions Linux

To verify the version of Adobe Flash Player installed on your system, access the About Flash Player page, or right- click on content running in Flash Player and select "About Adobe (or Macromedia) Flash Player" from the menu. If you use multiple browsers, perform the check for each browser you have installed on your system.

Mitigations

Beginning with Flash Player 27, administrators have the ability to change Flash Player's behavior when running on Internet Explorer on Windows 7 and below by prompting the user before playing SWF content.  For more details, see this administration guide.   

Administrators may also consider implementing Protected View for Office.  Protected View opens a file marked as potentially unsafe in Read-only mode.  

Vulnerability details

Vulnerability Category Vulnerability Impact Severity CVE Number
Use-after-free Remote Code Execution Critical CVE-2018-4878

Acknowledgments

Adobe would like to thank KrCERT/CC for reporting this issue and for working with Adobe to help protect our customers. 

Revisions

February 8, 2018: Added a reference to APSB18-03, which announced the update (28.0.0.161) that resolved CVE-2018-4878.  Also added a note indicating that the ActiveX component in Adobe Connect was not impacted by CVE-2018-4878.