CVE-2021-21017
Acrobat Reader DC Heap-based Buffer Overflow Vulnerability Could Lead To Arbitrary Code Execution
- High 8.8
- Exploited: added to CISA KEV 3 Nov 2021
Description
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.
Key facts
- Published
- 11 Feb 2021
- Last changed
- 21 Oct 2025
- Assigned by
- adobe
- KEV added
- 3 Nov 2021
- KEV fix due
- 17 Nov 2021
- EPSS
- 86.274% likely to be exploited in the next 30 days, higher than 99.739% of CVEs (scores for 15 Nov 2026)
- SSVC (CISA)
- Exploitation: active; Automatable: no; Technical impact: total
Severity scores
Each score is shown as its source gave it. They are not averaged or merged.
- 8.8CVSS 3.1, Highfrom the CNA (adobe)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
What to do
- Apply updates per vendor instructions.CISA KEV required action
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Adobe | Acrobat Reader |
|
Timeline
- 11 Feb 2021 Published
- 3 Nov 2021 CVE-2021-21017 added to CISA KEV
- 3 Nov 2021 Added to the CISA KEV catalogue