# CVE-2021-28550: Adobe Acrobat and Reader Use-After-Free Vulnerability

CVE-2021-28550 is fixed in Adobe Acrobat Reader DC on 1 platform by Adobe Acrobat Reader DC 21.001.20155 (version 21.001.20155), released April 27, 2021. It is being exploited: CISA added it to the Known Exploited Vulnerabilities catalog on November 3, 2021. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/cve/CVE-2021-28550
- Priority: Patch now
- CVSS: 8.8
- EPSS: 0.5213
- CISA KEV: listed Nov 3, 2021, federal due date Nov 17, 2021
- Exploited (vendor report): yes
- Publicly disclosed: no
- Published: Sep 2, 2021
- Weakness: CWE-416: Use After Free (CWE-416)
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-28550

## Description

Acrobat Reader DC versions versions 2021.001.20150 (and earlier), 2020.001.30020 (and earlier) and 2017.011.30194 (and earlier) are affected by a Use After Free 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Adobe Acrobat Reader DC | 21.001.20155 | [Adobe Acrobat Reader DC 21.001.20155](https://patchblox.com/security/data/fix/windows-app/adobe.acrobat.reader.32-bit-21.001.20155.md) | Apr 27, 2021 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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