Medium severity · published Feb 18, 2026
CVE-2026-20139
Client-Side Denial of Service (DoS) through ''/splunkd/__raw/services/authentication/users/username'' REST API endpoint in Splunk Enterprise
4.3
CVSS
5.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)5.7% · higher than 93% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SC
Splunk Cloud Platform · Splunk
10.2.2510 before 10.2.2510.3; 10.1.2507 before 10.1.2507.8; 10.0.2503 before 10.0.2503.9; 9.3.2411 before 9.3.2411.121 · source: vendor, NVD
SE
Splunk Enterprise · Splunk
10.0 before 10.0.2; 9.4 before 9.4.8; 9.3 before 9.3.9; 9.2 before 9.2.12 · source: vendor
SP
Splunk · Splunk
9.2.0 before 9.2.12; 9.3.0 before 9.3.9; 9.4.0 before 9.4.8; 10.0.0 before 10.0.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-20139
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-20139
Vendor Advisory
https://advisory.splunk.com/advisories/SVD-2026-0204
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