CVE-2021-28640

published 2021-08-20

CVE-2021-28640: Acrobat Reader DC versions 2021.005.20054 (and earlier), 2020.004.30005 (and earlier) and 2017.011.30197 (and earlier) are affected by an Use-after-free…

Priority P3 57 high 7.3 CVSS 3.1

AV L AC L PR L 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 an Use-after-free vulnerability. An authenticated 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-2021-28640 is a Use-After-Free vulnerability in Adobe Acrobat and Reader leading to arbitrary code execution; detection should focus on exploitation of malicious PDF files opened by a victim user ↗
• → Exploitation requires user interaction — a victim must open a malicious file; monitor for suspicious PDF file opens triggering Acrobat Reader DC processes with anomalous child process spawning ↗
• → Affected versions to flag in asset inventory and endpoint telemetry: Acrobat DC Continuous 2021.005.20054 and earlier, Acrobat 2020 Classic 2020.004.30005 and earlier, Acrobat 2017 Classic 2017.011.30197 and earlier (Windows and macOS) ↗
• → Successful exploitation leads to arbitrary code execution in the context of the current user; monitor for unexpected code execution or process injection originating from AcroRd32.exe or Acrobat.exe ↗

• · Both Windows and macOS platforms are affected; ensure detection coverage spans both OS environments ↗

CVSS provenance

nvd v3.1 7.3 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

nvd v2.0 6.0 MEDIUM AV:N/AC:M/Au:S/C:P/I:P/A:P

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