CVE-2021-39856: Adobe Acrobat Reader DC NTLMv2 SSO Information Disclosure via LoadFile

Published Sep 29, 2021
·
Updated

Acrobat Reader DC ActiveX Control versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by an Information Disclosure vulnerability. An unauthenticated attacker could leverage this vulnerability to obtain NTLMv2 credentials. Exploitation of this issue requires user interaction in that a victim must visit an attacker controlled web page.

Affected Software

24 affected components
Adobe Acrobat>=17.011.30059<=17.011.30199
Adobe Acrobat Reader>=17.011.30059<=17.011.30199
Apple macOS
Microsoft Windows
Adobe Acrobat>=20.001.30005<=20.004.30006
Adobe Acrobat Reader>=20.001.30005<=20.004.30006
Adobe Acrobat DC>=15.008.20082<=21.005.20058
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20058
Adobe Acrobat DC>=15.008.20082<=21.005.20060
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20060
All of the following
Any of the following
Adobe Acrobat>=17.011.30059<=17.011.30199
Adobe Acrobat Reader>=17.011.30059<=17.011.30199
Any of the following
Apple macOS
Microsoft Windows
All of the following
Any of the following
Adobe Acrobat>=20.001.30005<=20.004.30006
Adobe Acrobat Reader>=20.001.30005<=20.004.30006
Any of the following
Apple macOS
Microsoft Windows
All of the following
Any of the following
Adobe Acrobat DC>=15.008.20082<=21.005.20058
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20058
Apple macOS
All of the following
Any of the following
Adobe Acrobat DC>=15.008.20082<=21.005.20060
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20060
Microsoft Windows

Event History

Sep 29, 2021
CVE Published
via MITRE·03:39 PM
Data Sourced
via MITRE·03:39 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-39856?

CVE-2021-39856 is classified as an Information Disclosure vulnerability that could lead to the exposure of NTLMv2 credentials.

2

How do I fix CVE-2021-39856?

The fix for CVE-2021-39856 is to update Adobe Acrobat Reader DC to a version that is not affected, specifically versions newer than 2021.005.20060.

3

What versions of Adobe Acrobat Reader are affected by CVE-2021-39856?

CVE-2021-39856 affects Adobe Acrobat Reader DC versions 2021.005.20060 and earlier, 2020.004.30006 and earlier, and 2017.011.30199 and earlier.

4

Can CVE-2021-39856 be exploited remotely?

Yes, CVE-2021-39856 can be exploited by an unauthenticated attacker to gain sensitive information.

5

What systems are at risk with CVE-2021-39856?

CVE-2021-39856 affects installations of Adobe Acrobat and Acrobat Reader on various operating systems, particularly if not updated to the latest versions.

Contact

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