Failure to Sanitize Special Elements into a Different Plane (Special Element Injection) Affecting github.com/nuclio/nuclio/pkg/processor/runtime/shell package, versions <1.15.20
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-GOLANG-GITHUBCOMNUCLIONUCLIOPKGPROCESSORRUNTIMESHELL-15440716
- published9 Mar 2026
- disclosed4 Mar 2026
- creditb0b0haha, j311yl0v3u
Introduced: 4 Mar 2026
CVE-2026-29042 Â (opens in a new tab)How to fix?
Upgrade github.com/nuclio/nuclio/pkg/processor/runtime/shell to version 1.15.20 or higher.
Overview
Affected versions of this package are vulnerable to Failure to Sanitize Special Elements into a Different Plane (Special Element Injection) in the processing of the X-Nuclio-Arguments HTTP header, which is incorporated into shell commands without validation or sanitization. An attacker can execute arbitrary commands with root privileges in function containers, steal sensitive tokens, and gain full control over the Kubernetes cluster by sending specially crafted HTTP requests containing malicious shell metacharacters.
Workaround
This vulnerability can be mitigated by disabling the Shell Runtime in the platform configuration, restricting function deployment permissions using RBAC, or applying network isolation to limit egress from function pods.