2021-34842 | Foxit PDF Reader Annotation Object use after free

By Max On Aug 8, 2021

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6.7	$0-$5k	0.52

A vulnerability classified as critical was found in Foxit PDF Reader 11.0.0.49893 (Document Reader Software). This vulnerability affects an unknown code of the component Annotation Object Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-416. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Foxit PDF Reader 11.0.0.49893. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the handling of Annotation objects. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-14024.

The weakness was published 08/05/2021. The advisory is shared for download at zerodayinitiative.com. This vulnerability was named CVE-2021-34842 since 06/17/2021. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading eliminates this vulnerability.

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