CVE-2026-20255 | Improper Input Validation through Classic Dashboards in Splunk Enterprise

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. The vulnerability exists because URL validation on the external content dialog is incomplete, which can allow for requests to untrusted domains when a user interacts with a crafted dashboard.

Published: 2026-06-10 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

NVD Status：Analyzed，CVE State: published

View at NVD, CVE.org, EUVD

Threat Intelligence & Risk Assessment for CVE-2026-20255

EPSS CVSS CWE GHSA Affected

Conclusion & alert: CVE-2026-20255 is rated Low Risk (28.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.24%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-20255

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.04%	0.24%	+0.19%
2	2026-06-11	—	0.04%	—

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-20255

CVSS metrics for this CVE.

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.7	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	2.1	3.6	[email protected]

Weakness enumeration for CVE-2026-20255

CWE-20 MITRE ↗

GitHub Security Advisory for CVE-2026-20255

GHSA-hw35-mvfj-v86g · Severity: medium — In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform...

Affected software / configurations for CVE-2026-20255

Vendor	Product	Version	Raw CPE
splunk	splunk	>= 9.3.0, < 9.3.13	cpe:2.3:a:splunk:splunk:::::enterprise:::*
splunk	splunk	>= 9.4.0, < 9.4.12	cpe:2.3:a:splunk:splunk:::::enterprise:::*
splunk	splunk	>= 10.0.0, < 10.0.7	cpe:2.3:a:splunk:splunk:::::enterprise:::*
splunk	splunk	>= 10.2.0, < 10.2.4	cpe:2.3:a:splunk:splunk:::::enterprise:::*
splunk	splunk_cloud_platform	>= 9.3.2411, < 9.3.2411.132	cpe:2.3:a:splunk:splunk_cloud_platform::::::::
splunk	splunk_cloud_platform	>= 10.1.2507, < 10.1.2507.23	cpe:2.3:a:splunk:splunk_cloud_platform::::::::
splunk	splunk_cloud_platform	>= 10.2.2510, < 10.2.2510.15	cpe:2.3:a:splunk:splunk_cloud_platform::::::::
splunk	splunk_cloud_platform	>= 10.3.2512, < 10.3.2512.13	cpe:2.3:a:splunk:splunk_cloud_platform::::::::

References for CVE-2026-20255

URL	Tags
https://advisory.splunk.com/advisories/SVD-2026-0605	Vendor Advisory

cvelogic Threat Intelligence