# CVE-2020-8178: Command injection in jison

> Insufficient input validation in the jison library allows attackers to execute arbitrary OS commands via crafted input.

- **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:** 15 Jul 2020
- **Updated:** 4 Aug 2024
- **Also known as:** OESA-2022-1546, OESA-2022-2046, UBUNTU-CVE-2020-8178

## What is CVE-2020-8178?

CVE-2020-8178 is a critical command injection vulnerability in jison, published on 15 Jul 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Insufficient input validation in npm package `jison` <= 0.4.18 may lead to OS command injection attacks.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2020-8178?

It affects 1 product.


Products: Jison Project Jison.

## How do I fix CVE-2020-8178?

Upgrade to a fixed version.

## Is CVE-2020-8178 being exploited?

There is no known exploitation of CVE-2020-8178 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-8178 and fix it if it is affected.

What it is: CVE-2020-8178 is a critical command injection vulnerability in jison, published on 15 Jul 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-2020-8178 in the wild and no public exploit code.

Affected product: jison. 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-2020-8178/ (Markdown: https://insights.sbomify.com/CVE-2020-8178/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-8178
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-8178
- OSV: https://osv.dev/vulnerability/CVE-2020-8178

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-8178/
Summaries are generated and may contain mistakes; the official description above is the record.