CVE-2026-20257 json
Improper Input Validation through Classic Dashboard CSS in Splunk Enterprise
published 2026-06-10 4 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-36085
- cvss
- 5.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 22%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Splunk Splunk Enterprise 9.3.13, 9.4.12, 10.0.7, 10.2.4
- Splunk Splunk Cloud Platform 9.3.2411.132, 10.1.2507.23, 10.2.2510.15, 10.3.2512.13
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N |
Affected products
- Splunk Splunk Enterprise
- Splunk Splunk Cloud Platform
Classification
- Weakness
-
- CWE-20 Improper Input Validation
References
-
advisory.splunk.com
/advisories/SVD-2026-0607
vendor-advisory
Sources
- CVE List CVE-2026-20257
- NVD CVE-2026-20257
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