# CVE-2018-13818: Code injection in n/a

> Server-Side Template Injection in Twig allows attackers to execute arbitrary code via the search_key parameter if input is not properly sanitized by the application.

- **Severity:** Critical 9.8 (`CVSS:3.0/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:** No
- **Published:** 10 Jul 2018
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-rgff-87c8-rh44

## What is CVE-2018-13818?

CVE-2018-13818 is a critical code injection vulnerability in n/a, published on 10 Jul 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Twig before 2.4.4 allows Server-Side Template Injection (SSTI) via the search search_key parameter. NOTE: the vendor points out that Twig itself is not a web application and states that it is the responsibility of web applications using Twig to properly wrap input to it

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

## Which versions are affected by CVE-2018-13818?

It affects 1 product.


Products: Symfony Twig.

## How do I fix CVE-2018-13818?

No fix has been published for CVE-2018-13818 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-13818 being exploited?

There is no known exploitation of CVE-2018-13818 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2026-46633](https://insights.sbomify.com/CVE-2026-46633/): Twig: PHP code injection via `{% use %}` template name (high 8.7)
- [CVE-2026-46640](https://insights.sbomify.com/CVE-2026-46640/): Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation (high 8.7)
- [CVE-2026-24425](https://insights.sbomify.com/CVE-2026-24425/): Twig 2.16.x & 3.9.0-3.25.x Sandbox Bypass via SourcePolicyInterface (high 8.7)
- [CVE-2024-45411](https://insights.sbomify.com/CVE-2024-45411/): Twig has a possible sandbox bypass (high 8.6)
- [CVE-2026-46634](https://insights.sbomify.com/CVE-2026-46634/): Twig: `template_from_string()` escapes a SourcePolicy-driven sandbox via synthesized template name (high 7.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-13818 and fix it if it is affected.

What it is: CVE-2018-13818 is a critical code injection vulnerability in n/a, published on 10 Jul 2018. 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-2018-13818 in the wild and no public exploit code.

Affected product: n/a. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2018-13818/ (Markdown: https://insights.sbomify.com/CVE-2018-13818/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-13818
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-13818
- OSV: https://osv.dev/vulnerability/CVE-2018-13818

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-13818/
Summaries are generated and may contain mistakes; the official description above is the record.