CISA KEV · Known exploitedHigh

CVE-2021-28550

Adobe Acrobat and Reader

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.

CVSS: 8.8
EPSS: 52.0%
CISA KEV: Listed
Published: 2021.09.03

PRIORITY ASSESSMENT

Immediate review

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.

Known exploitationConfirmed by CISA KEV

Exploit probability52.0%

Technical severityCVSS 8.8

Vulnerability overview

Affected product and versions

Product: Adobe Acrobat and Reader
Affected versions: unspecified, >= 15.008.20082 <= 21.001.20150, >= 17.011.30059 <= 17.011.30194, >= 20.001.30005 <= 20.001.30020, >= 15.008.20082 <= 21.001.20149
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

CISA required action

Apply updates per vendor instructions.

Due date: 2021.11.17

1
Identify
Confirm that Adobe Acrobat and Reader and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE: CWE-416
KEV added: 2021.11.03
Ransomware use: 미확인