2021-38569 | Foxit PhantomPDF/Reader XFA Form infinite loop

By Max On Aug 16, 2021

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5.6	$0-$5k	0.48

A vulnerability classified as problematic was found in Foxit PhantomPDF and Reader up to 10.1.3 (Document Reader Software). This vulnerability affects some unknown functionality of the component XFA Form Handler. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-835. As an impact it is known to affect availability. CVE summarizes:

An issue was discovered in Foxit Reader and PhantomPDF before 10.1.4. It allows stack consumption via recursive function calls during the handling of XFA forms or link objects.

The weakness was presented 08/12/2021. The advisory is available at foxitsoftware.com. This vulnerability was named CVE-2021-38569 since 08/11/2021. 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. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 10.1.4 eliminates this vulnerability.

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