CVE-2025-20382 is a vulnerability identified in Splunk Enterprise versions below 10.0.2, 9.4.6, 9.3.8, and 9.2.10, as well as Splunk Cloud Platform versions below 10.1.2507.10, 10.0.2503.8, and 9.3.2411.120. The issue arises because a low-privileged user, lacking admin or power roles, can create a views dashboard that includes a custom background image using the 'data:image/png;base64' protocol. This crafted input can circumvent Splunk's external URL warning mechanism, leading to an unvalidated redirect vulnerability. Essentially, the vulnerability allows an attacker to embed a specially crafted URL that redirects authenticated users to an external malicious site without triggering the usual warnings. Exploitation requires the attacker to trick a victim into initiating a request within their browser, meaning user interaction (phishing) is necessary. The vulnerability does not allow the attacker to exploit the system arbitrarily or escalate privileges but facilitates phishing by simplifying redirection to malicious sites. The CVSS v3.1 score is 3.5 (low severity), reflecting the limited impact on confidentiality (partial information disclosure risk), no impact on integrity or availability, low complexity, and requirement for user interaction and privileges. There are no known exploits in the wild at this time. The vulnerability is primarily a phishing enabler rather than a direct compromise vector.

For European organizations, the primary impact of CVE-2025-20382 is an increased risk of phishing attacks leveraging trusted Splunk dashboards to redirect users to malicious external sites. This could lead to credential theft, malware installation, or further social engineering attacks. Since Splunk is widely used in security monitoring, IT operations, and critical infrastructure sectors, a successful phishing campaign exploiting this vulnerability could undermine trust in security dashboards and potentially expose sensitive operational data indirectly. The vulnerability does not allow direct system compromise or data integrity violations but can facilitate lateral attack vectors through phishing. Organizations in sectors such as finance, energy, telecommunications, and government, which heavily rely on Splunk for monitoring and incident response, could face elevated risks. The requirement for authenticated access and user interaction limits the scope but does not eliminate the threat, especially in environments with many users having low-privileged Splunk accounts.

1. Upgrade affected Splunk Enterprise and Splunk Cloud Platform instances to the patched versions: 10.0.2 or later for Enterprise, and 10.1.2507.10 or later for Cloud. 2. Restrict the ability to create or modify dashboards with custom backgrounds to trusted users only, minimizing the risk of malicious dashboard creation. 3. Implement strict content security policies (CSP) and URL filtering on Splunk dashboards to prevent loading or redirecting to untrusted external URLs. 4. Educate users about phishing risks, especially regarding unexpected redirects from internal dashboards or monitoring tools. 5. Monitor Splunk logs for unusual dashboard creation or modification activities by low-privileged users. 6. Use multi-factor authentication (MFA) to reduce the risk of compromised credentials being used in phishing attacks. 7. Consider network segmentation and web proxy controls to block access to known malicious external sites that could be used in redirects. These measures go beyond generic patching by focusing on reducing the attack surface and improving detection and response capabilities.