CVE-2021-28635

published 2021-08-20

CVE-2021-28635: Acrobat Reader DC versions 2021.005.20054 (and earlier), 2020.004.30005 (and earlier) and 2017.011.30197 (and earlier) are affected by a use-after-free…

Priority P3 58 high 7.8 CVSS 3.1

AV L AC L PR N UI R S U C H I H A H

Acrobat Reader DC versions 2021.005.20054 (and earlier), 2020.004.30005 (and earlier) and 2017.011.30197 (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.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
adobe	acrobat_dc	15.008.20082 – 21.005.20054	—
adobe	acrobat_dc	17.011.30059 – 17.011.30197	—
adobe	acrobat_dc	20.001.30005 – 20.004.30005	—
adobe	acrobat_reader	unspecified – 2020.004.30005	—
adobe	acrobat_reader_dc	15.008.20082 – 21.005.20054	—
adobe	acrobat_reader_dc	17.011.30059 – 17.011.30197	—
adobe	acrobat_reader_dc	20.001.30005 – 20.004.30005	—

Detection & IOCs extracted from sources · hover to see the quote

• → CVE-2021-28635 is a Use-After-Free vulnerability in Adobe Acrobat and Reader leading to arbitrary code execution; detect suspicious child processes spawned by Acrobat/Reader processes as a sign of exploitation ↗
• → Exploitation requires a victim to open a malicious file; monitor for suspicious PDF file opens in Acrobat Reader DC versions 2021.005.20054 and earlier, 2020.004.30005 and earlier, and 2017.011.30197 and earlier ↗

• · Affected versions span three release tracks; ensure version detection covers all three tracks: Acrobat DC Continuous, Acrobat 2020 Classic, and Acrobat 2017 Classic ↗
• · Vulnerability affects both Windows and macOS platforms; detection and patching coverage must include both operating systems ↗

CVSS provenance

nvd v3.1 7.8 HIGH CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

nvd v2.0 9.3 CRITICAL AV:N/AC:M/Au:N/C:C/I:C/A:C

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