CVE-2025-20384Network attack vector

Unauthenticated log poisoning via ANSI escape injection

Published Dec 3, 2025 · Updated Dec 3, 2025

Log injection in Splunk Web allows remote attackers to corrupt Splunk Enterprise and Splunk Cloud Platform logs via HTTP requests. The /en-US/static/ endpoint writes unvalidated ANSI escape codes from crafted requests into Splunk log files. No authentication is required, but Splunk Web must be enabled; successful injection can poison, forge, or obfuscate records and impair detection.

CVSS severity5.3
Medium
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Log injection in Splunk Web allows remote attackers to corrupt Splunk Enterprise and Splunk Cloud Platform logs via HTTP requests. The /en-US/static/ endpoint writes unvalidated ANSI escape codes from crafted requests into Splunk log files. No authentication is required, but Splunk Web must be enabled; successful injection can poison, forge, or obfuscate records and impair detection.

The record

CVE
CVE-2025-20384
Published
Dec 3, 2025
Updated
Dec 3, 2025
Vendor
Splunk, Inc.
Product
Splunk Enterprise
Classifications
CWE-117, CAPEC-81, CAPEC-93, CAPEC-268, T1562
Attack vector
network
Privileges
unauthenticated

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 <10.0.1
  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 privilegesunauthenticated

What is affected?

Splunk, Inc. · Splunk Enterpriseversion=10.0 <10.0.1; version=9.2 <9.2.10; version=9.3 <9.3.8; version=9.4 <9.4.6
Zoom Video Communications, Inc. · Splunk Cloud Platformversion=10.0.2503 <10.0.2503.6; version=10.1.2507 <10.1.2507.4; version=9.3.2411 <9.3.2411.117

Published CVSS scores

5.3SplunkCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-117Improper Output Neutralization for Logs
CAPEC-81Web Server Logs Tampering
CAPEC-93Log Injection-Tampering-Forging
CAPEC-268Audit Log Manipulation
T1562Impair Defenses

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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