CVE-2026-20254 Information Disclosure through External Content Restriction Bypass in Splunk Enterprise
Low-privileged users can exfiltrate sensitive data to external servers by bypassing content restrictions via CSS injection in crafted dashboards viewed by higher-privileged users.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-20254?
CVE-2026-20254 is a medium-severity vulnerability in Splunk Splunk, published on 10 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user that does not hold the 'admin' or 'power' Splunk roles could craft a malicious classic dashboard that exfiltrates sensitive data to an external server when a higher-privileged user views it, bypassing the external content restriction through a Cascading Style Sheets (CSS) injection.<br><br>The Trusted Domains security check does not fully validate inline style attribute values, which can allow for outbound requests to untrusted domains and credential exfiltration when a victim views a crafted dashboard.
Weakness: CWE-20
Which versions are affected by CVE-2026-20254?
It affects 2 products.
Products include Splunk Splunk, Splunk Splunk Cloud Platform.
How do I fix CVE-2026-20254?
No fix has been published for CVE-2026-20254 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-20254 being exploited?
There is no known exploitation of CVE-2026-20254 in the wild and no public exploit code.
Other vulnerabilities in Splunk Splunk
- CVE-2026-20253 Splunk Enterprise Missing Authentication for Critical Function
- CVE-2026-76268 Missing Authentication for Critical Function in the Patroni REST API in Splunk Enterprise
- CVE-2026-76284 Improper Neutralization in Splunk Enterprise
- CVE-2026-76285 Improper Adherence to Coding Standards in Splunk Enterprise
- CVE-2017-17067 Auth bypass in n/a
Sources
Also known as GHSA-c58f-cc4q-2mvj.