What is CVE-2021-28550?

CVE-2021-28550 is a critical-severity vulnerability in Adobe Acrobat Reader, classified under Use After Free. CVSS score: 9.6/10. Published 2021-09-02.

How severe is CVE-2021-28550?

Critical severity. CVSS v3 base score is 9.6 out of 10.

Is CVE-2021-28550 known to be exploited?

Yes. CVE-2021-28550 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 14 public proof-of-concept repositories are indexed.

Use After Free in Adobe Acrobat Reader

CVE-2021-28550

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 t…

Vulnerability class: Use-After-Free

EPSS: 0.307 (96.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.

Affected products

Adobe Acrobat Reader — versions unspecified

Weakness classification (CWE)

CWE-416 — Use After Free

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2021-11-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2021-11-17.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

helpx.adobe.com/security/products/acrobat/apsb21-29.html

Frequently asked questions

What is CVE-2021-28550?: CVE-2021-28550 is a critical-severity vulnerability in Adobe Acrobat Reader, classified under Use After Free. CVSS score: 9.6/10. Published 2021-09-02.
How severe is CVE-2021-28550?: Critical severity. CVSS v3 base score is 9.6 out of 10.
Is CVE-2021-28550 known to be exploited?: Yes. CVE-2021-28550 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 14 public proof-of-concept repositories are indexed.