GHSA-2c83-wfv3-q25f

Source

https://github.com/advisories/GHSA-2c83-wfv3-q25f

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/09/GHSA-2c83-wfv3-q25f/GHSA-2c83-wfv3-q25f.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-2c83-wfv3-q25f

Published

2021-09-07T23:07:56Z

Modified

2021-09-07T14:04:47Z

Summary

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in ZMarkdown

Details

Impact

A Remote Command Execution vulnerability was found in the rebber module, which allowed execution of arbitrary commands. The reported problem came from CodeBlocks, which could be escaped to insert malicious LaTeX.

Anyone using rebber without sanitation of code content or a custom macro is impacted by this vulnerability. Here is an example of a Markdown content that will exploit the vulnerability:

```
\end{CodeBlock}

\immediate\write18{COMMAND > outputrce}
\input{outputrce}

\begin{CodeBlock}{text}
```

Will insert into the generated LaTeX the result of executing COMMAND on the system.

Patches

The vulnerability has been patched in version 5.2.1. If impacted, you should update to this version as soon as possible.

Workarounds

It is possible to mitigate the vulnerability without upgrading by using a custom code macro. Please make sure this custom macro escapes your closing LaTeX sequence. For the example above, use:

const escaped = content.replace(new RegExp('\\\\end\\s*{CodeBlock}', 'g'), '')

For more information

If you have any questions or comments about this advisory, open an issue in ZMarkdown.

Database specific

{
    "cwe_ids": [
        "CWE-78"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-09-07T14:04:47Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
}

References

Affected packages

npm / rebber

Package

Name: rebber; View open source insights on deps.dev
Purl: pkg:npm/rebber

Affected ranges

Type: SEMVER
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

5.2.1

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/09/GHSA-2c83-wfv3-q25f/GHSA-2c83-wfv3-q25f.json"