No exploitation reportedFix available

CVE-2026-20204

Q: Is CVE-2026-20204 actively exploited?

Active exploitation of CVE-2026-20204 has not been confirmed. Its EPSS score was 3.1% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2026-20204?

CVE-2026-20204 has a CVSS v3 base score of 7.1 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2026-04-15
Fixed in10.3.2512.5 · 10.2.2510.9 · 10.1.2507.19 · 10.0.2503.13 · 9.3.2411.127
WeaknessCWE-377

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

In Splunk Enterprise versions below 10.2.1, 10.0.5, 9.4.10, and 9.3.11, and Splunk Cloud Platform versions below 10.4.2603.0, 10.3.2512.5, 10.2.2510.9, 10.1.2507.19, 10.0.2503.13, and 9.3.2411.127, a low-privileged user that does not hold the `admin` or `power` Splunk roles could potentially perform a Remote Code Execution (RCE) by uploading a malicious file to the `$SPLUNK_HOME/var/run/splunk/apptemp` directory due to improper handling and insufficient isolation of temporary files within the `apptemp` directory.

Timeline

dates in UTC

2026-04-1516:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-20204?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-20204?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Splunk splunk cloud platform

Branch	Affected	Fixed in	Source
10.3	≥ 10.3.2512, < 10.3.2512.5	10.3.2512.5	NVD
10.2	≥ 10.2.2510, < 10.2.2510.9	10.2.2510.9	NVD
10.1	≥ 10.1.2507, < 10.1.2507.19	10.1.2507.19	NVD
10.0	≥ 10.0.2503, < 10.0.2503.13	10.0.2503.13	NVD
9.3	≥ 9.3.2411, < 9.3.2411.127	9.3.2411.127	NVD

Splunk

Branch	Affected	Fixed in	Source
10.0	≥ 10.0.0, < 10.0.5	10.0.5	NVD
9.4	≥ 9.4.0, < 9.4.10	9.4.10	NVD
9.3	≥ 9.3.0, < 9.3.11	9.3.11	NVD
10.2	= 10.2.0	no fix published	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Splunk splunk cloud platform to 10.3.2512.5 · 10.2.2510.9 · 10.1.2507.19 · 10.0.2503.13 · 9.3.2411.127

Advisories and patches

advisory.splunk.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVE recordread 2026-10-23
CISA-ADPSSVC decisionnone2026-04-15
OpenCVESSVC decisionnone—
CNACVSS 3.17.1read 2026-10-23
CNAweakness (CWE)CWE-377read 2026-10-23
FIRST EPSSEPSS score3.1 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
Published: 2026-04-15
Last Modified: 2026-06-17
NVD status: Analyzed

Frequently asked questions

What is CVE-2026-20204?

Is CVE-2026-20204 actively exploited?

Active exploitation of CVE-2026-20204 has not been confirmed. Its EPSS score was 3.1% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-20204?

CVE-2026-20204 has a CVSS v3 base score of 7.1 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H.

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