CVE-2026-20258 Stored Cross-Site Scripting (XSS) through Classic Dashboard in Splunk Enterprise
Low-privileged users can inject malicious scripts into Splunk dashboards, executing code in victims' browsers via phishing.
- 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-2026-20258?
CVE-2026-20258 is a high-severity cross-site scripting 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 10.3.2512.11, 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 store a malicious script in a classic dashboard HTML panel, causing unauthorized JavaScript code to execute in the browser of another user.
The vulnerability requires the attacker to phish the victim by tricking them into initiating a request within their browser. The low-privileged user should not be able to exploit the vulnerability at will.
Weakness: CWE-79
Which versions are affected by CVE-2026-20258?
It affects 2 products.
Products include Splunk Splunk, Splunk Splunk Cloud Platform.
How do I fix CVE-2026-20258?
No fix has been published for CVE-2026-20258 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-20258 being exploited?
There is no known exploitation of CVE-2026-20258 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-xg25-vr2h-r356.