SPL Command Safeguards Bypass via the ‘collect’ SPL Command Aliases in Splunk Enterprise

Description

In Splunk Enterprise versions below 8.1.13, 8.2.10, and 9.0.4, aliases of the ‘collect’ search processing language (SPL) command, including ‘summaryindex’, ‘sumindex’, ‘stash’,’ mcollect’, and ‘meventcollect’, were not designated as safeguarded commands. The commands could potentially allow for the exposing of data to a summary index that unprivileged users could access. The vulnerability requires a higher privileged user to initiate a request within their browser, and only affects instances with Splunk Web enabled.

Solution

For Splunk Enterprise, upgrade versions to 8.1.13, 8.2.10, 9.0.4, or higher.

For Splunk Cloud Platform, Splunk is actively patching and monitoring the Splunk Cloud instances.

Product Status

Mitigations and Workarounds

If users do not log in to Splunk Web on indexers in a distributed environment, disable Splunk Web on those indexers. See Disable unnecessary Splunk Enterprise components and the web.conf configuration specification file for more information on disabling Splunk Web.

Detections

• Splunk Risky Command Abuse disclosed February 2023

This hunting search provides information on potential abuse of the ‘collect’ SPL command.

Severity

Splunk rated the vulnerability as Medium, 6.3, with a CVSSv3.1 vector of CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N. The ’collect’ aliases have limited write capabilities, but could write confidential data to a summary index that all users can access, such as the default summary index.

If the Splunk Enterprise instance does not run Splunk Web, there is no impact and the severity is Informational.

Acknowledgments

James Ervin, Splunk