The vulnerability CVE-2025-30553 in Z.com byGMO's GMO Font Agent is a stored cross-site scripting issue caused by improper input neutralization during web page generation. This allows an attacker with at least low privileges and requiring user interaction to inject malicious scripts that can lead to partial confidentiality, integrity, and availability impacts. The affected versions are up to 1.6. No patch or remediation details are provided in the available data.

Successful exploitation can lead to execution of arbitrary scripts in the context of the affected web application, potentially resulting in partial compromise of confidentiality, integrity, and availability of the affected system or user data. The CVSS vector indicates network attack vector, low attack complexity, low privileges required, user interaction required, and scope change, with low impact on confidentiality, integrity, and availability.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. In the absence of an official fix, users should monitor vendor communications for updates. Until a patch is available, consider applying input validation or output encoding controls if possible to mitigate stored XSS risks in the GMO Font Agent component.