CVE-2026-76277Network attack vectorHinoki check available

Account configuration collisions via trailing-period usernames

Published Oct 7, 2026 · Updated Oct 7, 2026

Improper username validation in Splunk Enterprise 9.4, 10.0, 10.2, and 10.4 releases lets remote authenticated users disrupt account management. Its REST API accepts a native username ending in a period before using that name for a user directory, allowing distinct usernames to share per-user configuration data. A role with the edit_user capability is required; subsequent user-management operations can affect the wrong account or fail.

CVSS severity4.1
Medium
EPSS probability0.18%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Improper username validation in Splunk Enterprise 9.4, 10.0, 10.2, and 10.4 releases lets remote authenticated users disrupt account management. Its REST API accepts a native username ending in a period before using that name for a user directory, allowing distinct usernames to share per-user configuration data. A role with the edit_user capability is required; subsequent user-management operations can affect the wrong account or fail.

The record

CVE
CVE-2026-76277
Published
Oct 7, 2026
Updated
Oct 7, 2026
Vendor
Splunk, Inc.
Product
Splunk Enterprise
Classifications
CWE-20, T1098
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Oct 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 7, 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 <10.0.10
  2. Affected versionversion=10.2 <10.2.7
  3. Affected versionversion=10.4 <10.4.3
  4. Affected versionversion=9.4 <9.4.15

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Splunk, Inc. · Splunk Enterpriseversion=10.0 <10.0.10; version=10.2 <10.2.7; version=10.4 <10.4.3; version=9.4 <9.4.15

Published CVSS scores

4.1Splunk, Inc.CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1098Account Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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