CVE-2026-1542 is a vulnerability classified under CWE-502 (Deserialization of Untrusted Data) affecting the Super Stage WP WordPress plugin versions through 1.0.1. The plugin unserializes user-supplied data from the REQUEST superglobal without proper validation or sanitization. This unsafe deserialization can be exploited by unauthenticated remote attackers to perform PHP Object Injection attacks if the target WordPress installation contains a suitable gadget chain—code that can be abused during object deserialization to execute malicious actions. PHP Object Injection can lead to a range of impacts including data manipulation, information disclosure, or even remote code execution depending on the available gadgets and application logic. The vulnerability does not require authentication or user interaction and can be triggered remotely over the network, increasing its risk profile. The CVSS v3.1 base score is 6.5, indicating a medium severity with network attack vector, low attack complexity, no privileges required, no user interaction, and limited confidentiality and integrity impact but no availability impact. No patches or known exploits are currently reported, but the vulnerability is publicly disclosed and should be addressed promptly. The plugin's widespread use in WordPress environments makes this a relevant threat for many organizations relying on this CMS and plugin combination.

The primary impact of CVE-2026-1542 is the potential compromise of data confidentiality and integrity within affected WordPress sites using the Super Stage WP plugin. Attackers can inject crafted serialized objects to manipulate application behavior, potentially exposing sensitive information or altering data. While remote code execution is not explicitly confirmed, the presence of suitable gadget chains could escalate the impact. This vulnerability can be exploited remotely without authentication, increasing the attack surface and risk to organizations worldwide. Compromised sites could be used for further attacks such as privilege escalation, data theft, or as a foothold for lateral movement within networks. The lack of availability impact reduces the risk of denial-of-service conditions but does not diminish the seriousness of data integrity and confidentiality concerns. Organizations running vulnerable versions of the plugin are at risk of targeted or opportunistic attacks, especially those with high-value data or critical web infrastructure.

To mitigate CVE-2026-1542, organizations should first check for plugin updates or patches from the vendor and apply them immediately once available. In the absence of patches, disabling or removing the Super Stage WP plugin is recommended. Implement strict input validation and sanitization to prevent unserializing untrusted data, especially from user-controllable sources like REQUEST. Employ web application firewalls (WAFs) with rules designed to detect and block malicious serialized payloads or PHP Object Injection attempts. Review and harden PHP configurations to disable dangerous functions or limit object deserialization where possible. Conduct code audits to identify and remove gadget chains that could be exploited. Monitor logs for unusual activity indicative of exploitation attempts, such as unexpected serialized data or abnormal plugin behavior. Educate development teams on secure coding practices regarding serialization and deserialization. Finally, maintain regular backups and incident response plans to quickly recover from potential compromises.