# CVE-2020-9296: Expression Language Injection in Netflix Conductor

> Attackers can execute arbitrary Java code by injecting malicious expressions into custom constraint violation error message templates in Netflix Titus.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Jun 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-wfj5-2mqr-7jvv

## What is CVE-2020-9296?

CVE-2020-9296 is a critical code injection vulnerability in Netflix Titus, published on 16 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Netflix Titus uses Java Bean Validation (JSR 380) custom constraint validators. When building custom constraint violation error messages, different types of interpolation are supported, including Java EL expressions. If an attacker can inject arbitrary data in the error message template being passed to ConstraintValidatorContext.buildConstraintViolationWithTemplate() argument, they will be able to run arbitrary Java code.

Weakness: CWE-917 (Improper Neutralization of Special Elements used in an Expression Language Statement)

## Which versions are affected by CVE-2020-9296?

2 open source packages ship an affected version, including com.netflix.conductor:conductor-core. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `com.netflix.conductor:conductor-core` | Maven | All versions | 2.25.4 |
| `com.netflix.conductor:conductor-core` | Maven | All versions | 2.25.4 |

Products: Netflix Conductor.

## How do I fix CVE-2020-9296?

Upgrade com.netflix.conductor:conductor-core to 2.25.4 or later.

## Is CVE-2020-9296 being exploited?

There is no known exploitation of CVE-2020-9296 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-9296 and fix it if it is affected.

What it is: CVE-2020-9296 is a critical code injection vulnerability in Netflix Titus, published on 16 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-9296 in the wild and no public exploit code.

Affected packages and fixed versions:
- com.netflix.conductor:conductor-core (Maven): affected all versions; fixed in 2.25.4
- com.netflix.conductor:conductor-core (Maven): affected all versions; fixed in 2.25.4

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-2020-9296/ (Markdown: https://insights.sbomify.com/CVE-2020-9296/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-9296
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-9296
- OSV: https://osv.dev/vulnerability/CVE-2020-9296

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-9296/
Summaries are generated and may contain mistakes; the official description above is the record.