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CVE-2021-21017

8.8
HIGHCVSS v3.1 Base Score
90.20%
HIGH RiskEPSS (100th percentile)
KEV

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.

Published: 2/11/2021
Modified: 10/23/2025
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ACTIVELY EXPLOITED IN THE WILD

This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Vulnerability Name:

Adobe Acrobat and Reader Heap-based Buffer Overflow Vulnerability

Vendor / Product:

Adobe Acrobat and Reader

Required Action:

Apply updates per vendor instructions.

Due Date: 11/17/2021(OVERDUE)
Added to KEV:

11/3/2021

Notes:

https://nvd.nist.gov/vuln/detail/CVE-2021-21017

Vulnerability Summary

CVSS v3 Score

8.8HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS v2 Score

6.8

AV:N/AC:M/Au:N/C:P/I:P/A:P

EPSS Score (Exploitation Probability)

90.20%HIGH Exploitation Risk
100th percentile

This vulnerability has a 90.20% probability of being exploited in the next 30 days, ranking higher than 100% of all scored CVEs.

CWE Classification

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