CVE-2025-59845 is a high-severity cross-site request forgery (CSRF) vulnerability affecting Apollo GraphQL's Embeddable Explorer and Embeddable Sandbox products prior to versions 3.7.3 and 2.7.2 respectively. These products are embeddable web components that allow users to interact with GraphQL APIs directly from a web page. The vulnerability stems from missing origin validation in the client-side code that processes window.postMessage events. Specifically, the embeddable components fail to verify the origin of incoming postMessage events, allowing a malicious website to send crafted messages to the embedding page. Because the victim’s browser is authenticated with the GraphQL server via cookies, the attacker can leverage this flaw to execute arbitrary GraphQL queries or mutations on behalf of the victim without their consent. This can lead to unauthorized data access or modification. The vulnerability is categorized under CWE-346 (Origin Validation Error) and CWE-352 (Cross-Site Request Forgery). The CVSS v3.1 base score is 8.2, reflecting a high impact on integrity and confidentiality, with no privileges required but user interaction needed (visiting a malicious site). No known exploits have been reported in the wild as of the publication date. The issue has been addressed by Apollo in versions 2.7.2 (Sandbox) and 3.7.3 (Explorer), which implement proper origin validation to prevent unauthorized postMessage handling.

For European organizations, this vulnerability poses a significant risk, especially for those using Apollo GraphQL's embeddable tools to facilitate API exploration or testing within internal or customer-facing portals. Exploitation could allow attackers to perform unauthorized GraphQL operations, potentially exposing sensitive data or altering backend data stores. This could lead to data breaches, loss of data integrity, and compliance violations under GDPR due to unauthorized access or modification of personal data. The attack requires a user to visit a malicious website, which could be delivered via phishing or malicious ads, making it a plausible vector in targeted or opportunistic attacks. Organizations relying on these embeddable components in their web applications or developer tools should consider the risk of lateral movement or privilege escalation within their environments. The lack of known exploits suggests limited immediate threat, but the high CVSS score and ease of exploitation warrant prompt remediation to avoid potential future attacks.

1. Immediate upgrade of Apollo Sandbox to version 2.7.2 or later and Apollo Explorer to version 3.7.3 or later to ensure the vulnerability is patched. 2. Review all web applications embedding these Apollo GraphQL components to confirm they use updated versions. 3. Implement Content Security Policy (CSP) directives to restrict the domains allowed to embed or communicate with these components, reducing the risk of malicious postMessage injections. 4. Conduct security awareness training to educate users about the risks of visiting untrusted websites that could exploit CSRF vulnerabilities. 5. Monitor GraphQL server logs for unusual or unauthorized queries or mutations that could indicate exploitation attempts. 6. If upgrading is not immediately feasible, consider disabling or removing the embeddable components until patched versions can be deployed. 7. Apply network-level controls to restrict outbound connections to known malicious domains to reduce exposure to phishing or drive-by attacks that could trigger exploitation.