CVE-2026-25497 is a privilege escalation vulnerability identified in the Craft CMS platform, specifically affecting its GraphQL API's saveAsset mutation. Craft CMS is widely used for building digital experiences and managing content. The vulnerability exists in versions from 4.0.0-RC1 up to before 4.17.0-beta.1 and 5.9.0-beta.1. The core issue stems from improper authorization validation: while the mutation checks permissions against the schema-resolved asset volume, it retrieves the target asset by its ID without confirming that the asset belongs to the authorized volume. This discrepancy allows an authenticated user with write permissions on one asset volume to escalate privileges and modify or transfer assets belonging to other volumes, including those marked as restricted or private. This cross-volume authorization bypass violates the principle of least privilege and can lead to unauthorized data exposure or tampering. The vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key). The CVSS 4.0 base score is 8.6 (high severity), reflecting network exploitability, low attack complexity, no required user interaction, and significant impact on confidentiality and integrity. No known exploits are reported in the wild as of the publication date. The issue is resolved in Craft CMS versions 4.17.0-beta.1 and 5.9.0-beta.1, where proper asset ownership verification is enforced during the saveAsset mutation.

For European organizations using affected versions of Craft CMS, this vulnerability poses a significant risk to the confidentiality and integrity of digital assets managed within the CMS. Attackers with authenticated write access to any asset volume can manipulate or transfer assets from other volumes, potentially exposing sensitive or restricted content. This can lead to unauthorized data disclosure, content defacement, intellectual property theft, or disruption of digital services. Organizations in sectors such as media, e-commerce, government, and education that rely on Craft CMS for content management are particularly at risk. The ability to escalate privileges within the CMS can also facilitate further lateral movement or compromise within the organization's digital infrastructure. Given the network-exploitable nature and lack of required user interaction, the vulnerability could be exploited remotely by insiders or compromised accounts, increasing the threat surface. Failure to patch may result in reputational damage, regulatory non-compliance (e.g., GDPR breaches due to unauthorized data access), and financial losses.

European organizations should immediately assess their Craft CMS deployments to identify affected versions (>= 4.0.0-RC1 and < 4.17.0-beta.1, and >= 5.0.0-RC1 and < 5.8.22). The primary mitigation is to upgrade to Craft CMS versions 4.17.0-beta.1 or later, or 5.9.0-beta.1 or later, where the vulnerability is patched. Until upgrades are applied, organizations should restrict write access to asset volumes to only trusted and necessary users, enforce strong authentication and account monitoring to detect suspicious activity, and consider implementing additional application-layer access controls or Web Application Firewall (WAF) rules to monitor and block suspicious GraphQL mutation requests. Regularly audit asset volume permissions and logs for unauthorized modifications. Additionally, organizations should review their incident response plans to quickly address potential exploitation and data breaches related to this vulnerability. Coordination with CMS administrators and developers is critical to ensure timely patching and configuration hardening.