CVE-2025-67809 identifies a security weakness in Zimbra Collaboration Suite (ZCS) versions 10.0 and 10.1, specifically within the Flickr Zimlet integration. The Flickr Zimlet contained hardcoded API credentials (API key and secret) embedded directly in its publicly accessible code. This practice violates secure credential management principles (CWE-798) by exposing sensitive authentication secrets to any party able to access the Zimlet code. An attacker can extract these credentials and impersonate the legitimate Zimbra Flickr integration, initiating valid OAuth authorization flows with Flickr. If a user is deceived into approving such an OAuth request, the attacker gains access to the user's Flickr data, compromising confidentiality and integrity of that data. The vulnerability does not provide direct access to Zimbra systems or escalate privileges but leverages social engineering and OAuth mechanisms to access third-party user data. The attack vector is network-based, requires no privileges, but demands user interaction and has high attack complexity due to the need to trick users into approving OAuth requests. The scope is limited to users of the Flickr Zimlet in affected Zimbra versions. The vendor has removed the hardcoded credentials and revoked the compromised Flickr API key, mitigating the issue in newer releases. No known exploits are reported in the wild as of now.

For European organizations, the primary impact lies in the potential unauthorized access to Flickr user data linked to corporate accounts or employees using the Flickr Zimlet. This could lead to exposure of sensitive images or metadata, potentially violating privacy regulations such as GDPR if personal data is involved. While the vulnerability does not compromise Zimbra servers directly, the misuse of OAuth tokens could undermine user trust and lead to reputational damage. Organizations relying on Zimbra Collaboration with Flickr integration may face increased phishing or social engineering risks as attackers attempt to trick users into approving malicious OAuth requests. The medium severity reflects limited direct system impact but notable confidentiality concerns. Availability and integrity of Zimbra services remain unaffected. The risk is heightened in environments where Flickr is actively used for business or employee collaboration.

European organizations should immediately upgrade Zimbra Collaboration Suite to versions beyond 10.1 where the hardcoded Flickr API credentials have been removed and revoked. If upgrading is not immediately feasible, disabling the Flickr Zimlet integration is recommended to prevent exposure. User education is critical: train users to recognize and reject suspicious OAuth authorization requests, especially those that appear unexpectedly or from untrusted sources. Implement monitoring of OAuth token usage and Flickr API access logs to detect anomalous activity. Employ network controls to restrict access to Zimbra Zimlet resources if possible. Review and audit all third-party integrations for hardcoded credentials or insecure practices. Finally, ensure incident response plans include steps for OAuth-related compromises and data privacy breach notifications under GDPR.