Cyber Resilience

CVE-2026-20258

High

Published: 10 June 2026

Published
10 June 2026
Modified
15 June 2026
KEV Added
Patch
CVSS Score v3.1 7.1 CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0017 7.0th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-20258 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Splunk Splunk. Its CVSS base score is 7.1 (High).

Operationally, ranked at the 7.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

splunk
splunk
9.3.0 — 9.3.13 · 9.4.0 — 9.4.12 · 10.0.0 — 10.0.7
splunk
splunk cloud platform
9.3.2411 — 9.3.2411.132 · 10.1.2507 — 10.1.2507.23 · 10.2.2510 — 10.2.2510.15

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References