---
title: "CVE-2021-28550: Adobe Acrobat Reader use after free… | CubePath"
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…"
language: en
source: https://cubepath.com/security/cve/CVE-2021-28550
---

# CVE-2021-28550: Adobe Acrobat Reader use after free… | CubePath

## 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.

Official description from the CVE record, published by adobe. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-28550)

## Key data

### CVSS 3.0 Critical 9.6

Score published by adobe in the CVE record.

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

| Metric                 | Value    | What it means                                                                       |
| ---------------------- | -------- | ----------------------------------------------------------------------------------- |
| Attack vector          | Network  | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity      | Low      | No special conditions are needed. The attack can be repeated at will.               |
| Privileges required    | None     | No account or privileges are needed.                                                |
| User interaction       | Required | A user has to do something first, such as opening a file or following a link.       |
| Scope                  | Changed  | The impact can reach other components beyond the vulnerable one.                    |
| Confidentiality impact | High     | Serious or total effect on the secrecy of data.                                     |
| Integrity impact       | High     | Serious or total effect on the trustworthiness of data.                             |
| Availability impact    | High     | Serious or total effect on availability.                                            |

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) .

### EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score

0.52132 (52.1% probability)

Percentile

99.0%

Scores of

Nov 10, 2026

Model

v2026.06.15

### CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.

Name in the catalog

Adobe Acrobat and Reader Use-After-Free Vulnerability

Added to the catalog

Nov 3, 2021

Federal due date

Nov 17, 2021

### CISA assessment as of Feb 4, 2025

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation

Recorded by CISA as active

Automatable

no

Technical impact

total

### Weakness (CWE)

CWE catalog version 5.0.

CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license.

- [CWE-416](https://cwe.mitre.org/data/definitions/416.html) Use After Free

## Affected products

Products listed in the CVE record, as the CNA published them.

- Adobe Acrobat Reader

  - affected: unspecified up to 2020.001.30020
  - affected: unspecified up to 2021.001.20150
  - affected: unspecified up to 2017.011.30194
  - affected: unspecified up to None

## References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

- [helpx.adobe.com/security/products/acrobat/apsb21-29.html](https://helpx.adobe.com/security/products/acrobat/apsb21-29.html)

## Timeline

1. ID reserved Mar 16, 2021
2. Record published Sep 2, 2021
3. Added to CISA KEV Nov 3, 2021
4. Record last updated Oct 21, 2025

## Look up another CVE

## About CubePath

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Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:37 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)