Foxit PDF Reader 9.1.0.5096 XFA Element PDF Document out-of-bounds

Summaryinfo

A vulnerability classified as critical was found in Foxit PDF Reader 9.1.0.5096. Affected by this issue is some unknown functionality of the component XFA Element Handler. Such manipulation as part of PDF Document leads to out-of-bounds. This vulnerability is referenced as CVE-2018-3956. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Foxit PDF Reader 9.1.0.5096 (Document Reader Software). Affected by this issue is an unknown function of the component XFA Element Handler. The manipulation as part of a PDF Document leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

An exploitable out-of-bounds read vulnerability exists in the handling of certain XFA element attributes of Foxit Software's PDF Reader version 9.1.0.5096. A specially crafted PDF document can trigger an out-of-bounds read, which can disclose sensitive memory content and aid in exploitation when coupled with another vulnerability. An attacker needs to trick the user to open the malicious file to trigger this vulnerability. If the browser plugin extension is enabled, visiting a malicious site can also trigger the vulnerability.

The bug was discovered 01/03/2019. The weakness was published 01/30/2019 (Website). The advisory is shared for download at talosintelligence.com. This vulnerability is handled as CVE-2018-3956 since 01/02/2018. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 12 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 121246 (Foxit PhantomPDF < 8.3.9 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 371399 (Foxit Reader and PhantomPDF Multiple Vulnerabilities).

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (121246). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Document Reader Software

Vendor

• Foxit

Name

• PDF Reader

Version

• 9.1.0.5096

License

• free

Website

• Vendor: https://www.foxitsoftware.com/

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Once again VulDB remains the best source for vulnerability data.

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