# CVE-2026-52833: Nuclio: Unsanitized runtimeAttributes.repositories injected into Groovy build.gradle leads to build-time RCE

> Attackers can inject arbitrary Groovy code into build files via unsanitized repository attributes, leading to remote code execution during function builds.

- **Severity:** High 8.0 (`CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Sep 2026
- **Updated:** 2 Sep 2026
- **Also known as:** GHSA-3v79-m2cg-89ww, GO-2026-6004

## What is CVE-2026-52833?

CVE-2026-52833 is a high-severity code 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 1.16.5, Nuclio's Java runtime generates a build.gradle file during function builds using Go's text/template package. The template renders runtimeAttributes.repositories[] values with the {{ . }} action, which performs no escaping. An attacker can embed a closing brace (}) to break out of the repositories {} block and append arbitrary Groovy statements that execute unconditionally during the Gradle configuration phase. This issue has been patched in version 1.16.5.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2026-52833?

3 open source packages ship an affected version, including github.com/nuclio/nuclio.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/nuclio/nuclio` | Go | All versions | None |
| `github.com/nuclio/nuclio` | Go | All versions | 1.16.5 |
| `github.com/nuclio/nuclio` | Go | All versions | 1.16.5 |

## How do I fix CVE-2026-52833?

Upgrade github.com/nuclio/nuclio to 1.16.5 or later.

## Is CVE-2026-52833 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52833 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-52833 and fix it if it is affected.

What it is: CVE-2026-52833 is a high-severity code injection vulnerability in nuclio, published on 2 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52833 exists.

Affected packages and fixed versions:
- github.com/nuclio/nuclio (Go): affected all versions; no fix listed
- github.com/nuclio/nuclio (Go): affected all versions; fixed in 1.16.5
- github.com/nuclio/nuclio (Go): affected all versions; fixed in 1.16.5

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-52833/ (Markdown: https://insights.sbomify.com/CVE-2026-52833/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-52833
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-52833
- OSV: https://osv.dev/vulnerability/CVE-2026-52833

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-52833/
Summaries are generated and may contain mistakes; the official description above is the record.