Adobe Security Bulletin

Security update for Adobe Acrobat and Reader | APSB21-104

Bulletin ID

Date Published

Priority

APSB21-104

October 12, 2021

2

Summary

Adobe has released security updates for Adobe Acrobat and Reader for Windows and macOS. These updates address  multiple critical and moderate vulnerabilities. Successful exploitation could lead to arbitrary code execution in the context of the current user.  

 

Affected Versions

Product

Track

Affected Versions

Platform

Acrobat DC 

Continuous 

21.007.20095 and earlier versions

Windows

Acrobat Reader DC

Continuous 

21.007.20095 and earlier versions
 

Windows

Acrobat DC 

Continuous 

21.007.20096  and earlier versions          

macOS

Acrobat Reader DC

Continuous 

21.007.20096 and earlier versions          

macOS

 

 

 

 

Acrobat 2020

Classic 2020           

20.004.30015 and earlier versions

Windows & macOS

Acrobat Reader 2020

Classic 2020           

20.004.30015 and earlier versions

Windows & macOS

 

 

 

 

Acrobat 2017

Classic 2017

17.011.30202 and earlier versions          

Windows & macOS

Acrobat Reader 2017

Classic 2017

17.011.30202 and earlier versions          

Windows & macOS

For questions regarding Acrobat DC, please visit the Acrobat DC FAQ page

For questions regarding Acrobat Reader DC, please visit the Acrobat Reader DC FAQ page.

Solution

Adobe recommends users update their software installations to the latest versions by following the instructions below.    

The latest product versions are available to end users via one of the following methods:    

  • Users can update their product installations manually by choosing Help > Check for Updates.     

  • The products will update automatically, without requiring user intervention, when updates are detected.      

  • The full Acrobat Reader installer can be downloaded from the Acrobat Reader Download Center.     

For IT administrators (managed environments):     

  • Refer to the specific release note version for links to installers.     

  • Install updates via your preferred methodology, such as AIP-GPO, bootstrapper, SCUP/SCCM (Windows), or on macOS, Apple Remote Desktop and SSH.     

   

Adobe categorizes these updates with the following priority ratings and recommends users update their installation to the newest version:    

Product

Track

Updated Versions

Platform

Priority Rating

Availability

Acrobat DC

Continuous

21.007.20099

Windows and macOS

2

Acrobat Reader DC

Continuous

21.007.20099

Windows and macOS

2

Release Notes     

 

 

 

 

 

 

Acrobat 2020

Classic 2020           

20.004.30017

Windows and macOS     

2

Acrobat Reader 2020

Classic 2020           

20.004.30017

Windows and macOS     

2

 

 

 

 

 

 

Acrobat 2017

Classic 2017

17.011.30204

Windows and macOS

2

Acrobat Reader 2017

Classic 2017

17.011.30204

Windows and macOS

2

Vulnerability Details

Vulnerability Category Vulnerability Impact Severity CVSS base score 
CVSS vector
CVE Number

 

 

Use After Free (CWE-416)

 

 

 

 

Arbitrary code execution 
 
 

 

 

 

 

Critical

 

 

 

 

7.8 

 

 

 

 

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

 

 

 

 

CVE-2021-40728 

 

 

 

 

Out-of-bounds Read (CWE-125)

 

 

 

 

Privilege escalation 

 

 

 

 

Moderate

 

 

 

 

3.3 

 

 

 

 

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N 
 

 

 

 

 

CVE-2021-40729

 

 

Use After Free (CWE-416
Privilege escalation 
Moderate 3.3 CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
CVE-2021-40730
Out-of-bounds Write (CWE-787
Arbitrary code execution 
Critical
7.8 CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H 
CVE-2021-40731 

Acknowledgements

Adobe would like to thank the following for reporting these issues and for working with Adobe to help protect our customers:   

  • Habooblabs (CVE-2021-40728, CVE-2021-40729)
  • Kai Lu of Zscaler's ThreatLabz (CVE-2021-40729)
  • Anonymous working with Trend Micro Zero Day Initiative (CVE-2021-40730, CVE-2021-40731) 

Revisions

October 13th: Updated acknowledgements for CVE-2021-40729



 

 


For more information, visit https://helpx.adobe.com/security.html, or email PSIRT@adobe.com.

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