WordPress 4.9.7 Plugin Installation wp-content/uploads unrestricted upload

Summaryinfo

A vulnerability described as critical has been identified in WordPress 4.9.7. This issue affects some unknown processing of the file wp-content/uploads of the component Plugin Installation Handler. Executing a manipulation can lead to unrestricted upload. The identification of this vulnerability is CVE-2018-14028. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in WordPress 4.9.7 (Content Management System) and classified as critical. This vulnerability affects an unknown code block of the file wp-content/uploads of the component Plugin Installation Handler. The manipulation with an unknown input leads to a unrestricted upload vulnerability. The CWE definition for the vulnerability is CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In WordPress 4.9.7, plugins uploaded via the admin area are not verified as being ZIP files. This allows for PHP files to be uploaded. Once a PHP file is uploaded, the plugin extraction fails, but the PHP file remains in a predictable wp-content/uploads location, allowing for an attacker to then execute the file. This represents a security risk in limited scenarios where an attacker (who does have the required capabilities for plugin uploads) cannot simply place arbitrary PHP code into a valid plugin ZIP file and upload that plugin, because a machine's wp-content/plugins directory permissions were set up to block all new plugins.

The bug was discovered 08/03/2018. The weakness was shared 08/10/2018 (Website). The advisory is shared for download at securityfocus.com. This vulnerability was named CVE-2018-14028 since 07/12/2018. The attack can be initiated remotely. The requirement for exploitation is a single authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 05/01/2023). The MITRE ATT&CK project declares the attack technique as T1608.002.

The vulnerability was handled as a non-public zero-day exploit for at least 7 days. During that time the estimated underground price was around $5k-$25k.

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 SecurityFocus (BID 105060†). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Content Management System

Name

• WordPress

Version

• 4.9.7

License

• open-source

Website

• Product: https://wordpress.com/

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Once again VulDB remains the best source for vulnerability data.

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