CVE-2026-52831 Nuclio: Unsanitized cron trigger event headers/body injected into CronJob shell command leads to persistent RCE
Attackers can inject shell commands via cron trigger headers or body, leading to persistent remote code execution in Nuclio deployments.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-52831?
CVE-2026-52831 is a high-severity command injection vulnerability in nuclio, published on 2 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Nuclio is a "Serverless" framework for Real-Time Events and Data Processing. Prior to version 1.16.4, the Nuclio controller builds a curl invocation string for each cron trigger and stores it as the args of a Kubernetes CronJob container (/bin/sh, -c, <command>). Two fields in the trigger specification flow into this string without adequate sanitization: event.headers keys and event.body. This issue has been patched in version 1.16.4.
Weakness: CWE-78
Which versions are affected by CVE-2026-52831?
3 open source packages ship an affected version, including github.com/nuclio/nuclio.
| Package | Affected | Fixed in |
|---|---|---|
github.com/nuclio/nuclio Go | All versions | 0.0.0-20260601075854-3356b86a8bfa |
github.com/nuclio/nuclio Go | All versions | 0.0.0-20260601075854-3356b86a8bfa |
github.com/nuclio/nuclio Go | All versions | 0.0.0-20260601075854-3356b86a8bfa |
How do I fix CVE-2026-52831?
Upgrade github.com/nuclio/nuclio to 0.0.0-20260601075854-3356b86a8bfa or later.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-52831 being exploited?
There is no known exploitation of CVE-2026-52831 in the wild and no public exploit code.
Sources
Also known as GHSA-v5px-423j-pf7p, GO-2026-5946.