NVD / CVE Program· CNA cisco

CVE-2026-20253: Unauthenticated Arbitrary File Creation and Truncation in a PostgreSQL Sidecar Service Endpoint in Splunk Enterprise

Noroxi assessment

Priority: Now (action score 98/100)

CISA has confirmed exploitation in the wild (Jun 18, 2026). Remediation deadline for US federal agencies: Jun 21, 2026.
A ready-made attack module is public (Nuclei); exploiting it takes no special expertise.
Probability of exploitation in the next 30 days: 96.9% (FIRST EPSS); higher than 99.8% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
According to the record, no fixed version is available yet.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Patch today or shut off access. Until a fix is released, restrict access to the affected component and follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

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.

CriticalCVSS 9.8 · v3.1KEVWeaponized No fix recorded

Published: Jun 10, 2026
Updated: Jul 23, 2026
EPSS: 96.9% · 99th percentile
CWE: CWE-306

Report tools

JSON

Action score

Now

Patch today or shut off access.

CVSS: 39 / 40 · 9.8 / 10
CISA KEV: 30 / 30 · Listed
EPSS: 29 / 30 · 96.9%

CISA SSVC decision

Exploitation: active
Automatable: yes
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · cisco: 9.8; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Jun 18, 2026. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Jun 21, 2026.

Get told when this record changes

In CISA KEV: exploitation in the wild confirmed
Weaponized exploit exists
No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
splunk	splunk	cpe:2.3:a:splunk:splunk

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

splunk splunk10.0.0 and later · before 10.0.7
splunk splunk10.2.0 and later · before 10.2.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.

Splunk Splunk Enterprise
- 10.2 and later · before 10.2.4affected
- 10.0 and later · before 10.0.7affected

Same product

splunk: all records

Other highest-scoring records for the same primary product.

CVE-2018-11409Splunk through 7.0.1 allows information disclosure by appending __raw/services/server/info/server-info?output_mode=json to a query, as demon
60This week
CVE-2023-32707‘edit_user’ Capability Privilege Escalation
59Plan
CVE-2026-20251Remote Code Execution through Deserialization of Untrusted Data in Splunk Secure Gateway
45Plan

Published before and after this one in the same product

← EarlierCVE-2026-20240May 20, 2026 · Denial of Service through coldToFrozen.sh Script in Splunk Enterprise
26Monitor
← EarlierCVE-2026-20252Jun 10, 2026 · Server-Side Request Forgery (SSRF) through Dashboard Studio PDF Export in Splunk Enterprise
30Monitor
Later →CVE-2026-20254Jun 10, 2026 · Information Disclosure through External Content Restriction Bypass in Splunk Enterprise
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

Nuclei detection template ×1
Proof-of-concept repository on GitHub ×7

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Nuclei detection template	Nuclei template CVE-2026-20253	—
Proof-of-concept repository on GitHub	stars:13	2026-06-12
Proof-of-concept repository on GitHub	stars:5	2026-06-13
Proof-of-concept repository on GitHub	stars:0	2026-06-14
Proof-of-concept repository on GitHub	stars:0	2026-06-26
Proof-of-concept repository on GitHub	stars:0	2026-06-29
Proof-of-concept repository on GitHub	stars:0	2026-07-18
Proof-of-concept repository on GitHub	stars:0	2026-09-10

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

PublishedJun 10, 2026
First PoCJun 12, 2026+1 d
CISA KEVJun 18, 2026+7 d
TodayNov 3, 2026+146 d

EPSS, last 120 days+1% in 7 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Alex Hordijk (hordalex)

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-76268119 days apartMissing Authentication for Critical Function in the Patroni REST API in Splunk Enterprise
40Plan
CVE-2026-7635570 days apartUnauthenticated Information Disclosure through an Edge Processor Service Endpoint in Splunk Enterprise
30Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

CVE-2026-202510 days apartRemote Code Execution through Deserialization of Untrusted Data in Splunk Secure Gateway
45Plan
CVE-2026-202520 days apartServer-Side Request Forgery (SSRF) through Dashboard Studio PDF Export in Splunk Enterprise
30Monitor
CVE-2026-2020456 days apartImproper Handling and Insufficient Isolation of Specific Temporary Files in Splunk Enterprise
29Monitor
CVE-2026-2029735 days apartPath Traversal through 'explicit_appname' in the App Install REST Endpoint in Splunk Enterprise
28Monitor

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-26-0364 · Jun 11, 2026(Splunk Enterprise/Cloud/SOAR Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-306 · Missing Authentication for Critical Function

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Root cause

A function added for development or support ships to production without authentication. It often relies on the assumption that it is “only reachable from the internal network.”

The bug in code

The whole CWE-306 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1// Added for the support team
2app.post("/maintenance/reset", resetDevice);

Fixed

1if (config.maintenanceEnabled) {
2  app.post(
3    "/maintenance/reset",
4    requireSession, requireRole("admin"), resetDevice
5  );
6}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

advisory.splunk.com/advisories/SVD-2026-0603

Show all references (1 more)

www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20253

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records