CVE-2026-26940 Improper Validation of Specified Quantity in Input in Kibana Leading to Denial of Service
An authenticated user can cause a denial of service in Kibana by sending a crafted Timelion expression that triggers excessive memory allocation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-26940?
CVE-2026-26940 is a medium-severity denial of service vulnerability in Elastic Kibana, published on 19 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Improper Validation of Specified Quantity in Input (CWE-1284) in the Timelion visualization plugin in Kibana can lead Denial of Service via Excessive Allocation (CAPEC-130). The vulnerability allows an authenticated user to send a specially crafted Timelion expression that overwrites internal series data properties with an excessively large quantity value.
Weakness: CWE-1284
Which versions are affected by CVE-2026-26940?
It affects 1 product.
Products include Elastic Kibana.
How do I fix CVE-2026-26940?
Apply the vendor's patch.
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-2026-26940 being exploited?
There is no known exploitation of CVE-2026-26940 in the wild and no public exploit code.
Other vulnerabilities in Elastic Kibana
Sources
Also known as GHSA-xfph-vq69-5ww2, MINI-546p-38p6-8hjq, MINI-5qrq-9577-qcqf, MINI-5wqg-gmgm-335r, MINI-6f5f-fcxx-767p, MINI-8q2f-p772-c2g9 and 1 more.