CVE-2021-39840 - CVE House
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Status published High CVE-2021-39840

Adobe Acrobat Reader DC AcroForm Field Use-After-Free Remote Code Execution Vulnerability

Vulnerability Description

Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by a use-after-free vulnerability when processing AcroForms that could result in arbitrary code execution in the context of the current user. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Acrobat Reader
Vulnerable Versions:
unspecified

Timeline

Official Publish: September 29th, 2021
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weaknesses (CWE)

CWE-416

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1055 Process Injection
Defense Evasion
T1105 Ingress Tool Transfer
Command and Control
T1485 Data Destruction
Impact