CVE-2021-39856: Adobe Acrobat

Medium severity, CVSS 6.5. EPSS: 2.4% chance of exploitation in the next 30 days.

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 products

• Adobe Acrobat: from 17.011.30059, up to and including 17.011.30199; from 20.001.30005, up to and including 20.004.30006
• Adobe Acrobat DC: from 15.008.20082, up to and including 21.005.20058; from 15.008.20082, up to and including 21.005.20060
• Adobe Acrobat Reader: from 17.011.30059, up to and including 17.011.30199; from 20.001.30005, up to and including 20.004.30006
• Adobe Acrobat Reader DC: from 15.008.20082, up to and including 21.005.20058; from 15.008.20082, up to and including 21.005.20060

Published 2021-09-29. Last modified 2026-06-17.