Improper input validation in Splunk
CVE-2026-20255
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (26.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Splunk
- Splunk Cloud Platform — versions 10.3.2512, 10.2.2510, 10.1.2507
- Splunk Cloud Platform
- Splunk Enterprise — versions 10.2, 10.0, 9.4
Weakness classification (CWE)
References
- advisory.splunk.com/advisories/SVD-2026-0605 (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-20255?
- CVE-2026-20255 is a medium-severity vulnerability in Splunk, classified under Improper Input Validation. CVSS score: 5.7/10. Published 2026-06-10.
- How severe is CVE-2026-20255?
- Medium severity. CVSS v3 base score is 5.7 out of 10.