CVE-2021-40420 - CVE House
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Status published High CVE-2021-40420

A use-after-free vulnerability exists in the JavaScript engine of Foxit...

Vulnerability Description

A use-after-free vulnerability exists in the JavaScript engine of Foxit Software’s PDF Reader, version 11.1.0.52543. A specially-crafted PDF document can trigger the reuse of previously freed memory, which can lead to arbitrary code execution. An attacker needs to trick the user to open the malicious file to trigger this vulnerability. Exploitation is also possible if a user visits a specially-crafted, malicious site if the browser plugin extension is enabled.

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

Foxit
Vulnerable Versions:
Foxit Reader 11.1.0.52543

Timeline

Official Publish: February 4th, 2022
Last Modified: April 15th, 2025
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/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