Adobe Acrobat and Reader Heap-based Buffer Overflow Vulnerability

Added to KEV
2021-11-03
Federal due date
2021-11-17
Vendor
Adobe
Product
Acrobat and Reader
EPSS
99.6th percentile (score 0.902, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2021-21017

CISA short description

Acrobat Acrobat and Reader contain a heap-based buffer overflow vulnerability that could allow an unauthenticated attacker to achieve code execution in the context of the current user.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.