Multiple Vulnerabilities in Adobe Products Could Allow for Arbitrary Code Execution

DESCRIPTION:
Multiple vulnerabilities have been discovered in Adobe Products, the
most severe of which could allow for arbitrary code execution.

* Photoshop is Adobe’s flagship image editing software.
* Digital Editions is an e-book reader software program.
* Bridge is a free digital asset management app. It is a mandatory
component of Adobe Creative Suite, Adobe eLearning Suite, Adobe
Technical Communication Suite and Adobe Photoshop CS2 through CS6.
* RoboHelp is a help authoring tool.

Successful exploitation of the most severe of these vulnerabilities
could allow for arbitrary code execution. Depending on the privileges
associated with the user an attacker could then install programs; view,
change, or delete data; or create new accounts with full user rights.
Users whose accounts are configured to have fewer user rights on the
system could be less impacted than those who operate with administrative
user rights.

IMPACT:
Multiple vulnerabilities have been discovered in Adobe Photoshop,
Digital Editions, Bridge and RoboHelp, the most severe of which could
allow for arbitrary code execution. Details of these vulnerabilities are
as follows:

Adobe Photoshop
* Buffer Overflow, which could allow for arbitrary code execution.
(CVE-2021-28548, CVE-2021-28549)

Adobe Digital Editions
* Privilege Escalation, which could allow for arbitrary file system
write. (CVE-2021-21100)

Adobe Bridge
* Out-of-bounds read, which could allow for information disclosure.
(CVE-2021-21091)
* Improper Authorization, which could allow for privilege escalation.
(CVE-2021-21096)
* Memory Corruption, which could allow for arbitrary code execution.
(CVE-2021-21093, CVE-2021-21092)
* Out-of-bounds write, which could allow for arbitrary code execution.
(CVE-2021-21094, CVE-2021-21095)

Adobe RoboHelp
* Uncontrolled search path element, which could allow for privilege
escalation. (CVE-2021-21070)

Successful exploitation of the most severe of these vulnerabilities
could allow for arbitrary code execution. Depending on the privileges
associated with the user an attacker could then install programs; view,
change, or delete data; or create new accounts with full user rights.
Users whose accounts are configured to have fewer user rights on the
system could be less impacted than those who operate with administrative
user rights.

SYSTEM AFFECTED:
* Adobe Photoshop 2020 versions 21.2.6 and earlier
* Adobe Photoshop 2021 versions 22.3 and earlier
* Adobe Digital Editions versions 4.5.11.187245 and earlier
* Adobe Bridge versions 10.1.1 and earlier
* Adobe Bridge versions 11.0.1 and earlier
* Adobe RoboHelp versions RH2020.0.3 and earlier

RECOMMENDATIONS:
We recommend the following actions be taken:

* Install the updates provided by Adobe immediately after appropriate
testing.
* Run all software as a non-privileged user (one without administrative
privileges) to diminish the effects of a successful attack.
* Apply the Principle of Least Privilege to all systems and services.

REFERENCES:
https://helpx.adobe.com/security.html
https://helpx.adobe.com/security/products/photoshop/apsb21-28.html
https://helpx.adobe.com/security/products/Digital-Editions/apsb21-26.html
https://helpx.adobe.com/security/products/bridge/apsb21-23.html
https://helpx.adobe.com/security/products/robohelp/apsb21-20.html