CVE-2026-33378 Grafana Data Source Plugin: DoS (OOM) via Negative Interval Injection in $__timeGroup Macro
Attackers can cause an out-of-memory crash in Grafana by injecting negative intervals into the timeGroup macro, requiring a SQL datasource.
- 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-2026-33378?
CVE-2026-33378 is a medium-severity denial of service vulnerability in Grafana Grafana, published on 13 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Using the $__timeGroup macro, one can achieve an OOM by overloading the server. This requires a SQL datasource. If the server is set up to auto-restart, the impact is minimal or non-existent, as the attack can take upwards of half an hour to crash the server.
Weakness: CWE-400
Which versions are affected by CVE-2026-33378?
1 open source package ship an affected version, including grafana. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
grafana Bitnami | From 8.0.0 | 11.6.14, 12.2.8, 12.3.6, 12.4.3, 13.0.1 |
Products include Grafana Grafana.
How do I fix CVE-2026-33378?
Upgrade grafana to a fixed version for your release line: 11.6.14, 12.2.8, 12.3.6 or 12.4.3.
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-2026-33378 being exploited?
There is no known exploitation of CVE-2026-33378 in the wild and no public exploit code.
Other vulnerabilities in Grafana Grafana
Sources
Also known as BIT-grafana-2026-33378, CLSA-2026-1780478536, GHSA-rr8q-qwrv-9pf6, MINI-26f5-c2v7-qjx9, MINI-2qx3-c8hm-h69p, MINI-76rh-4cmv-chpp and 14 more.