CVE-2021-21017
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.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Adobe Acrobat and Reader Heap-based Buffer Overflow Vulnerability
Adobe Acrobat and Reader
Apply updates per vendor instructions.
11/3/2021
https://nvd.nist.gov/vuln/detail/CVE-2021-21017
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v2 Score
AV:N/AC:M/Au:N/C:P/I:P/A:P
EPSS Score (Exploitation Probability)
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
Related Vulnerabilities
Same Weakness Type(CWE-122)
ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 7.1.2-13 and 6.9.13-38, a heap buffer overflow vulnerability in the XBM image decoder (ReadXBMImage) allows an attacker to write controlled data past the allocated heap buffer when processing a maliciously crafted image file. Any operation that reads or identifies an image can trigger the overflow, making it exploitable via common image upload and processing pipelines. Versions 7.1.2-13 and 6.9.13-38 fix the issue.
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Exim before 4.99.1, with certain non-default rate-limit configurations, allows a remote heap-based buffer overflow because database records are cast directly to internal structures without validation.
Similar SeverityHIGH
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