CVE-2026-20253
Exploitation confirmed. First attested on 2026-06-15 by CISA-ADP, CISA KEV, GCVE · kevintel, GCVE · shadowserver.
- Published2026-06-10
- Fixed in10.2.4 · 10.0.7
- WeaknessCWE-306
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « 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 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.
Timeline
dates in UTC- 2026-06-1018:16CVE publishedNVD
- 2026-06-1505:15Listed as exploited by GCVEGCVE
- 2026-06-1505:15Exploitation first reportedGCVE
- 2026-06-18Added to the CISA KEV catalogCISA KEV
- 2026-06-1816:55SSVC exploitation set to activeCISA-ADP
- 2026-10-2319:23First public proof of conceptPoC-in-GitHub
- 2026-10-2319:23EPSS crossed 10 %FIRST EPSS
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-20253?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-20253?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 10.2 | ≥ 10.2.0, < 10.2.4 | 10.2.4 | NVD |
| 10.0 | ≥ 10.0.0, < 10.0.7 | 10.0.7 | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Splunk to 10.2.4 · 10.0.7
- CISA’s 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.due 2026-06-21
Advisories and patches
- advisory.splunk.comMitigation · Vendor Advisory
Detection
read 2026-10-23 19:25 UTC- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- 7 repositories, unverifiedwatchtowrlabs/watchTowr-vs-Splunk-CVE-2026-202530xBlackash/CVE-2026-20253HORKimhab/CVE-2026-20253fevar54/CVE-2026-20253-Splunk-Enterprise-Pre-Auth-RCE-pssec-io/CVE-2026-20253 PoC-in-GitHub
CISA Known Exploited Vulnerability
- Date Added
- 2026-06-18
- Patch Due Date
- 2026-06-21
- Ransomware Use
- Unknown
- 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.
Sources
- NVDCVE recordread 2026-10-23
- CISA KEVKEV entry2026-06-18
- GCVEexploitation2026-06-15
- CISA-ADPSSVC decisionactive2026-06-18
- OpenCVESSVC decisionactive—
- CNACVSS 3.19.8read 2026-10-23
- CNAweakness (CWE)CWE-306read 2026-10-23
- FIRST EPSSEPSS score96.9 %read 2026-10-23
- PoC-in-GitHubproof of concept7read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- 2026-06-10
- Last Modified
- 2026-07-23
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2026-20253?
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What is the CVSS score for CVE-2026-20253?
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