CVE-2026-20258

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.

CVSS v3.1 Score

7.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0017

Probability of exploitation

0.07%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
splunk	splunk	9.3.0 — 9.3.13
splunk	splunk	9.4.0 — 9.4.12
splunk	splunk	10.0.0 — 10.0.7
splunk	splunk	10.2.0 — 10.2.4
splunk	splunk_cloud_platform	9.3.2411 — 9.3.2411.132
splunk	splunk_cloud_platform	10.1.2507 — 10.1.2507.23
splunk	splunk_cloud_platform	10.2.2510 — 10.2.2510.15
splunk	splunk_cloud_platform	10.3.2512 — 10.3.2512.11

References

Advisories & Patches

https://advisory.splunk.com/advisories/SVD-2026-0608

Frequently Asked Questions

What is CVE-2026-20258? +

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. It has a CVSS v3.1 base score of 7.1 (HIGH).

How severe is CVE-2026-20258? +

CVE-2026-20258 has a CVSS v3.1 score of 7.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0017, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-20258? +

CVE-2026-20258 affects products from splunk, specifically: splunk, splunk_cloud_platform. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-20258? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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