Vulnerability · Published Jun 10, 2026 · Assigned by cisco
CVE-2026-20257Improper Input Validation through Classic Dashboard CSS in Splunk Enterprise
Medium 5.7
In plain English
A medium-severity improper input validation in Splunk Cloud Platform from Splunk. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities).
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 classic dashboard that exfiltrates sensitive data from the browser of a higher-privileged user who views it. The exfiltration is possible because classic dashboard panels do not fully validate style attribute values, which can allow for requests to reach external domains outside the configured Trusted Domains List. 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Splunk | Splunk Enterprise | 10.2 – before 10.2.410.0 – before 10.0.79.4 – before 9.4.129.3 – before 9.3.13 |
| Splunk | Splunk Cloud Platform | 10.3.2512 – before 10.3.2512.1310.2.2510 – before 10.2.2510.1510.1.2507 – before 10.1.2507.239.3.2411 – before 9.3.2411.132 |
Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N