CVE-2026-20253
CriticalExploitedPublic exploitIn Splunk Enterprise versions below 10.2.4 and 10.0.7, and Splunk Cloud Platform versions below 10.4.2604.3 and 10.2.2510.14, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint.<br
Published Jun 10, 2026 · Updated Jul 23, 2026 · Also known as EUVD-2026-36088, GHSA-xgm5-jh99-wc4v
Key Facts
Patch immediately- CVE-2026-20253 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Splunk, Splunk Cloud Platform, Splunk Enterprise.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 15, 2026. Public exploit code is available.
- EPSS estimates a 97% probability of exploitation in the next 30 days.
- Fixed versions are available, including Splunk Cloud Platform 10.2.2510.14, Splunk Cloud Platform 10.4.2604.3, Splunk Enterprise 10.0.7.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
97%
Higher than 99.8% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2026-20253 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Jun 18, 2026 | Jun 21, 2026 | Not reported |
| Industry KEV feed | Jun 15, 2026 | Jun 21, 2026 | Not reported |
| CIRCL KEV | Jun 18, 2026 | Jun 21, 2026 | Not reported |
| ENISA EUVD | Jun 18, 2026 | n/a | Not reported |
Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Affected Products
5 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| SplunkSplunk | See advisory | 10.0.7 |
| Splunk Cloud Platform | >= 10.4.2604 | 10.4.2604.3 |
| Splunk Enterprise | >= 10.2 | 10.2.4 |
Patched Releases
Splunk Cloud Platform
10.2.2510.14, 10.4.2604.3
Splunk Enterprise
10.0.7, 10.2.4
Splunk
10.0.7, 10.2.4
Timeline
Publicly disclosed
Jun 10, 2026
Added to Industry KEV feed
Jun 15, 2026
Added to CISA KEV
Jun 18, 2026
Added to CIRCL KEV
Jun 18, 2026
Added to ENISA EUVD
Jun 18, 2026
Last updated
Jul 23, 2026
Weakness Type
- CWE-306 Missing Authentication for Critical Function
References
- advisoryhttps://advisory.splunk.com/advisories/SVD-2026-0601
- advisoryhttps://advisory.splunk.com/advisories/SVD-2026-0602
- advisoryhttps://advisory.splunk.com/advisories/SVD-2026-0604
- advisoryhttps://advisory.splunk.com/advisories/SVD-2026-0605
- advisoryhttps://advisory.splunk.com/advisories/SVD-2026-0606
FAQ
Common Questions.
In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint.
Affected: Splunk; Splunk Cloud Platform versions >= 10.4.2604; Splunk Enterprise versions >= 10.2. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 15, 2026.
Yes. It was added on Jun 18, 2026 with a federal remediation due date of Jun 21, 2026.
Public exploit code is available.
Fixed versions are available, including Splunk Cloud Platform 10.2.2510.14, Splunk Cloud Platform 10.4.2604.3, Splunk Enterprise 10.0.7.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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