kleor Easy Timer Plugin up to 4.2.1 on WordPress Shortcode code injection

Summaryinfo

A vulnerability has been found in kleor Easy Timer Plugin up to 4.2.1 on WordPress and classified as critical. This affects an unknown function of the component Shortcode Handler. The manipulation leads to code injection. This vulnerability is documented as CVE-2025-9519. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in kleor Easy Timer Plugin up to 4.2.1 on WordPress. It has been rated as critical. This issue affects an unknown part of the component Shortcode Handler. The manipulation with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The Easy Timer plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 4.2.1 via the plugin's shortcodes. This is due to insufficient restriction of shortcode attributes. This makes it possible for authenticated attackers, with Editor-level access and above, to execute code on the server.

The weakness was released by Jonas Benjamin Friedli. It is possible to read the advisory at wordfence.com. The identification of this vulnerability is CVE-2025-9519 since 08/27/2025. The exploitation is known to be easy. The attack may be initiated remotely. The exploitation needs additional levels of successful authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/04/2025). The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

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 EUVD (EUVD-2025-26705). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• kleor

Name

• Easy Timer Plugin

Version

• 4.2.0
• 4.2.1

CPE 2.3info

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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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