CVE-2026-100849: AzuraCast before 0.23.8 SSRF Filter Bypass via Hostname and Private IPs

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-27 · updated 2026-09-28
Weakness: CWE-918

Description

AzuraCast is a self-hosted web radio management suite. In AzuraCast before 0.23.8, the station webhook URL validation in AbstractConnector::getValidUrl() (backend/src/Webhook/Connector/AbstractConnector.php), used by the Generic and Discord webhook connectors, rejects only URLs whose host is a literal link-local IP address (169.254.0.0/16 or fe80::/10). Loopback addresses and RFC1918 private ranges are not rejected, and any non-literal-IP hostname causes the IP parsing call to throw, which skips the check entirely. A user holding only the station-scoped WebHooks permission can therefore configure a webhook pointing at an internal, loopback, or private-network target and cause the server to issue an outbound HTTP POST containing the station's Now Playing data, resulting in server-side request forgery. The PUT /station/{id}/webhook/{id}/test endpoint allows the same low-privileged user to trigger the request on demand. At the time of the advisory no patched version was available.

Affected products

AzuraCast: before 0.23.8 — fixed in 0.23.8

How to fix

Upgrade to a fixed version: AzuraCast 0.23.8. Check the vendor advisory for mitigations.

References

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