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

Source: https://junglewise.ai/threats/cve-2021-28550-adobe-acrobat-and-reader-use-after-free-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-28550 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2021-11-03

Adobe Acrobat and Reader are affected by a use-after-free vulnerability that allows an unauthenticated attacker to execute arbitrary code. Exploitation requires a user to open a specially crafted malicious file.

Technologies: [Adobe Acrobat](https://junglewise.ai/threats/technologies/acrobat), [Adobe Reader](https://junglewise.ai/threats/technologies/reader). Vendors: [Adobe](https://junglewise.ai/threats/vendors/adobe).

## Quick answers

**Is CVE-2021-28550 exploited in the wild?** Yes. CVE-2021-28550 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-28550?** Critical severity, with a CVSS score of 8.8, published 3 November 2021.

**Which products and versions are affected?** Adobe Acrobat Reader DC 2021.001.20150 (and earlier); Adobe Acrobat Reader DC 2020.001.30020 (and earlier); Adobe Acrobat Reader DC 2017.011.30194 (and earlier); Adobe Acrobat DC 21.001.20150 (and earlier).

**Is there a fix for CVE-2021-28550?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2021-28550 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2021-28550?** Check whether you run Adobe Acrobat or Adobe Reader. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Adobe Acrobat Reader DC 2021.001.20150 (and earlier)
- Adobe Acrobat Reader DC 2020.001.30020 (and earlier)
- Adobe Acrobat Reader DC 2017.011.30194 (and earlier)
- Adobe Acrobat DC 21.001.20150 (and earlier)

## Timeline

- 2021-11-03: disclosed
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2021-11-03: exploited: Reported as exploited in the wild at time of publication.

## Related threats

- [Adobe Acrobat Reader denial-of-service via uncontrolled resource consumption](https://junglewise.ai/threats/cve-2026-82001-adobe-acrobat-reader-denial-of-service-via-uncontrolled-resource)
- [Adobe Acrobat Reader privilege escalation via incorrect authorization](https://junglewise.ai/threats/cve-2026-81996-adobe-acrobat-reader-privilege-escalation-via-incorrect)
- [Adobe Acrobat Reader prototype pollution arbitrary file read](https://junglewise.ai/threats/cve-2026-81994-adobe-acrobat-reader-prototype-pollution-arbitrary-file-read)
- [Adobe Acrobat Reader heap buffer overflow in PDF parsing](https://junglewise.ai/threats/cve-2026-81993-adobe-acrobat-reader-heap-buffer-overflow-in-pdf-parsing)
- [Adobe Acrobat Reader heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-81992-adobe-acrobat-reader-heap-based-buffer-overflow)