quarka QA Assistants Plugin up to 5.3.0 on WordPress wp-cron.php wrap_unserialize_static dlevent_ver/raw_name deserialization

Summaryinfo

A vulnerability was found in quarka QA Assistants Plugin up to 5.3.0. It has been rated as critical. This affects the function wrap_unserialize_static of the file wp-cron.php. The manipulation of the argument dlevent_ver/raw_name leads to deserialization. This vulnerability is uniquely identified as CVE-2026-87112. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in quarka QA Assistants Plugin up to 5.3.0. It has been rated as critical. This issue affects the function wrap_unserialize_static of the file wp-cron.php. The manipulation of the argument dlevent_ver/raw_name with an unknown input leads to a deserialization vulnerability. Using CWE to declare the problem leads to CWE-502. The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The QA Assistants – Driven by data plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 5.3.0 via the 'dlevent_ver' parameter. This is due to unrestricted PHP deserialization via wrap_unserialize_static() calling unserialize() without an allowed_classes restriction, combined with serialize_escape() failing to sanitize path traversal sequences in the raw_name parameter. This makes it possible for unauthenticated attackers to inject a PHP Object. The Guzzle FileCookieJar gadget present in the plugin's bundled Composer dependencies can be leveraged to perform an Arbitrary File Write, writing attacker-controlled content to an attacker-chosen filename, which can result in Remote Code Execution. Exploitation requires triggering the qahm_cron_data_manage scheduled event via wp-cron.php to invoke the deserialization sink against a planted queue file, but this endpoint requires no authentication and fires automatically on a two-minute schedule.

It is possible to read the advisory at wordfence.com. The identification of this vulnerability is CVE-2026-87112 since 09/08/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/07/2026).

By approaching the search of inurl:wp-cron.php it is possible to find vulnerable targets with Google Hacking.

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

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Productinfo

Type

• WordPress Plugin

Vendor

• quarka

Name

• QA Assistants Plugin

Version

• 5.0
• 5.1
• 5.2
• 5.3.0

CPE 2.3info

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CPE 2.2info

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