CVEs / CVE-2021-21017
CVE-2021-21017: Adobe Acrobat and Reader Heap-based Buffer Overflow Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- medium 6.8 CVSS 2.0 (NVD)
- EPSS 86.3% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Adobe Acrobat Reader | from unspecified, up to and including 2020.013.20074 | — |
| Adobe Acrobat Reader | from unspecified, up to and including 2020.001.30018 | — |
| Adobe Acrobat Reader | from unspecified, up to and including 2017.011.30188 | — |
| Adobe Acrobat Reader | from unspecified, up to and including None | — |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 17 Nov 2021 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 2.0 | 6.8 mediumAV:N/AC:M/Au:N/C:P/I:P/A:PScored by NVD |
|---|---|
| Weakness | CWE-122, CWE-787 |
References
- CVE-2021-21017 on NVD
- CVE-2021-21017 in the CISA KEV catalog
- https://helpx.adobe.com/security/products/acrobat/apsb21-09.html Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21017 Third Party Advisory, US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.