CVE-2026-20240 Denial of Service through coldToFrozen.sh Script in Splunk Enterprise
A low-privileged user can cause denial of service in Splunk Enterprise by exploiting missing input validation in a script to rename critical directories.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-20240?
CVE-2026-20240 is a high-severity denial of service vulnerability in Splunk Splunk, published on 20 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
In Splunk Enterprise versions below 10.2.2, 10.0.5, 9.4.11, and 9.3.12, and Splunk Cloud Platform versions below 10.4.2603.1, 10.3.2512.9, 10.2.2510.11, 10.1.2507.21, 10.0.2503.13, and 9.3.2411.129, a low-privileged user that does not hold the ‘admin’ or ‘power’ Splunk roles could cause a Denial of Service by exploiting the `coldToFrozen.sh` script in the `splunk_archiver` app to rename critical Splunk directories, making the instance non-functional.<br><br>The Denial of Service is possible because of missing input validation in the `coldToFrozen.sh` script, which accepts arbitrary file paths and renames them without restricting operations to safe directories.
Weakness: CWE-20
Which versions are affected by CVE-2026-20240?
It affects 2 products.
Products include Splunk Splunk, Splunk Splunk Cloud Platform.
How do I fix CVE-2026-20240?
No fix has been published for CVE-2026-20240 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-20240 being exploited?
There is no known exploitation of CVE-2026-20240 in the wild and no public exploit code.
Other vulnerabilities in Splunk Splunk
- CVE-2026-20253 Splunk Enterprise Missing Authentication for Critical Function
- CVE-2026-76268 Missing Authentication for Critical Function in the Patroni REST API in Splunk Enterprise
- CVE-2026-76284 Improper Neutralization in Splunk Enterprise
- CVE-2026-76285 Improper Adherence to Coding Standards in Splunk Enterprise
- CVE-2017-17067 Auth bypass in n/a
Sources
Also known as GHSA-2fmj-cw46-4vrm.