CVE-2025-20389Network attack vector

Client-side denial of service via crafted device label

Published Dec 3, 2025 · Updated Dec 3, 2025

Improper input validation in Splunk Secure Gateway allows remote authenticated users to cause client-side denial of service via a device label. The label column accepts a crafted payload when a user adds a device, but Splunk has not disclosed the exact validation operation that fails. Exploitation requires a low-privileged account and a registered device; the reported consequence is limited to interruption of the affected client.

CVSS severity4.3
Medium
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Splunk Secure Gateway allows remote authenticated users to cause client-side denial of service via a device label. The label column accepts a crafted payload when a user adds a device, but Splunk has not disclosed the exact validation operation that fails. Exploitation requires a low-privileged account and a registered device; the reported consequence is limited to interruption of the affected client.

The record

CVE
CVE-2025-20389
Published
Dec 3, 2025
Updated
Dec 3, 2025
Vendor
Splunk, Inc.
Product
Splunk Enterprise
Classifications
CWE-20, T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 3, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0 <10.0.2
  2. Affected versionversion=9.2 <9.2.10
  3. Affected versionversion=9.3 <9.3.8
  4. Affected versionversion=9.4 <9.4.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Splunk, Inc. · Splunk Enterpriseversion=10.0 <10.0.2; version=9.2 <9.2.10; version=9.3 <9.3.8; version=9.4 <9.4.6
Splunk, Inc. · Splunk Cloud Platformversion=10.0.2503 <10.0.2503.8; version=10.1.2507 <10.1.2507.6; version=9.3.2411 <9.3.2411.120
Splunk, Inc. · Splunk Secure Gatewayversion=3.7 <3.7.28; version=3.8 <3.8.58; version=3.9 <3.9.10

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.3SplunkCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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