CVE-2021-39856

Adobe Acrobat Reader DC NTLMv2 SSO Information Disclosure via LoadFile

Description

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.02% Top 20%
Vendor Advisory adobe.com
Affected: Adobe Acrobat Reader
Published at:
Updated at:

References

Link Tags
https://helpx.adobe.com/security/products/acrobat/apsb21-55.html release notes vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-39856?
CVE-2021-39856 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39856?
To fix CVE-2021-39856, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39856 being actively exploited in the wild?
It is possible that CVE-2021-39856 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39856?
CVE-2021-39856 affects Adobe Acrobat Reader.
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