CVE-2021-21017: Adobe Acrobat and Reader Heap-based Buffer Overflow Vulnerability

High severity, CVSS 8.8. Actively exploited: in CISA KEV since 2021-11-03. EPSS: 86.3% chance of exploitation in the next 30 days.

Acrobat Reader DC versions versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier) and 2017.011.30188 (and earlier) are affected by a heap-based buffer overflow vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Affected products

• Adobe Acrobat: from 17.0, up to and including 17.011.30188; from 20.0, up to and including 20.001.30018
• Adobe Acrobat DC: up to and including 20.013.20074
• Adobe Acrobat Reader: from 17.0, up to and including 17.011.30188; from 20.0, up to and including 20.001.300183
• Adobe Acrobat Reader DC: up to and including 20.013.20074

Published 2021-02-11. Last modified 2026-06-17.