Foo Labs Xpdf 4.00 PDF File Stream.cc DCTStream::getBlock null pointer dereference

Summaryinfo

A vulnerability classified as problematic has been found in Foo Labs Xpdf 4.00. The affected element is the function DCTStream::getBlock of the file Stream.cc of the component PDF File Handler. The manipulation leads to null pointer dereference. This vulnerability is uniquely identified as CVE-2018-18459. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Foo Labs Xpdf 4.00 (Document Reader Software). It has been rated as problematic. This issue affects the function DCTStream::getBlock of the file Stream.cc of the component PDF File Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

The function DCTStream::getBlock in Stream.cc in Xpdf 4.00 allows remote attackers to cause a denial of service (NULL pointer dereference) via a crafted pdf file, as demonstrated by pdftoppm.

The bug was discovered 10/16/2018. The weakness was disclosed 10/18/2018 (Website). It is possible to read the advisory at forum.xpdfreader.com. The identification of this vulnerability is CVE-2018-18459 since 10/18/2018. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 232032 (Linux Distros Unpatched Vulnerability : CVE-2018-18459), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (232032). The entries VDB-125742, VDB-125743, VDB-125744 and VDB-125745 are pretty similar. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Document Reader Software

Vendor

• Foo Labs

Name

• Xpdf

Version

• 4.00

License

• open-source

CPE 2.3info

• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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