SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-76277

The vulnerability is possible because username validation does not reject a trailing period before the username is used for a user directory.

MEDIUM 4.1EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

In Splunk Enterprise versions below 10.4.3, 10.2.7, 10.0.10, and 9.4.15, a user that holds a role with the edit_user capability could create a native Splunk username that ends with a period. The vulnerability is possible because username validation does not reject a trailing period before the username is used for a user directory. This can cause distinct native Splunk usernames to share per-user configuration data, and user-management operations can affect the wrong account or fail. For more information see Set up native Splunk authentication (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/use-the-native-splunk-platform-authentication-scheme/set-up-native-splunk-authentication) and Define roles on the Splunk platform with capabilities (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities) in the Splunk documentation.

CVSS 3.1
4.1 MEDIUMCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L
EPSS
0.24% probability · 16th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-20
Affected
splunk/splunk
Source
psirt@cisco.com
EPSS trend
0%3%5%8 October 2026: 0.18%26 October 2026: 0.24%8 October 202626 October 2026

EPSS moved from 0.2% on 8 October 2026 to 0.2% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.