CVE-2026-20139 json
Client-Side Denial of Service (DoS) through ''/splunkd/__raw/services/authentication/users/username'' REST API endpoint in Splunk Enterprise
published 8mo ago modified 4mo ago also EUVD-2026-8197
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 5.7%
- EPSS 5.7% chance of exploitation in 30 days, percentile 93%
- public exploits
- 0
- none known
Summary
In Splunk Enterprise versions below 10.2.0, 10.0.2, 9.4.8, 9.3.9, and 9.2.12, and Splunk Cloud Platform versions below 10.2.2510.3, 10.1.2507.8, 10.0.2503.9, and 9.3.2411.121, a low-privileged user that does not hold the "admin" or "power" Splunk roles could craft a malicious payload into the `realname`, `tz`, or `email` parameters of the `/splunkd/__raw/services/authentication/users/username` REST API endpoint when they change a password. This could potentially lead to a client‑side denial‑of‑service (DoS). The malicious payload might significantly slow page load times or render Splunk Web temporarily unresponsive.
Patch / fix
- Splunk Splunk Enterprise 9.2.12, 9.3.9, 9.4.8, 10.0.2
- Splunk Splunk Cloud Platform 9.3.2411.121, 10.0.2503.9, 10.1.2507.8, 10.2.2510.3
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 8mo ago
Exploit prediction
5.68% chance of exploitation in the next 30 days, higher than 93% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
Affected products
- Splunk Splunk Enterprise
- Splunk Splunk Cloud Platform
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
advisory.splunk.com
/advisories/SVD-2026-0204
vendor-advisory
Sources
- CVE List CVE-2026-20139
- NVD CVE-2026-20139
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