CVE-2026-20138

Duo MFA secret disclosure via internal logs

Published Feb 18, 2026 · Updated Feb 18, 2026

Sensitive information exposure in Splunk Enterprise allows remote authenticated users to read Duo MFA secrets from the _internal index. In Search Head Cluster deployments, splunkd writes the Duo integrationKey, secretKey, and appSecretKey values into searchable internal logs without redaction. Exposure requires Duo MFA and an authenticated role permitted to search _internal, and it discloses all three secrets in plaintext.

CVSS severity6.8
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive information exposure in Splunk Enterprise allows remote authenticated users to read Duo MFA secrets from the _internal index. In Search Head Cluster deployments, splunkd writes the Duo integrationKey, secretKey, and appSecretKey values into searchable internal logs without redaction. Exposure requires Duo MFA and an authenticated role permitted to search _internal, and it discloses all three secrets in plaintext.

The record

CVE
CVE-2026-20138
Published
Feb 18, 2026
Updated
Feb 18, 2026
Vendor
Zoom Video Communications, Inc.
Product
Splunk Enterprise
Classifications
CWE-532, T1552.001
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 18, 2026Record 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 <9.2.11
  3. Affected versionversion=9.3 <9.3.9
  4. Affected versionversion=9.4 <9.4.7

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

Zoom Video Communications, Inc. · Splunk Enterpriseversion=10.0 <10.0.2; version=9.2 <9.2.11; version=9.3 <9.3.9; version=9.4 <9.4.7

Published CVSS scores

6.8Cisco Systems, Inc.CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
4.9NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-532Insertion of Sensitive Information into Log File
T1552.001Credentials In Files

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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