AzuraCast: Server-Side Request Forgery
CVE-2026-100849 is a high-severity server-side request forgery vulnerability in AzuraCast, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 0.23.8 as the first without the flaw, so updating AzuraCast to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update AzuraCast to 0.23.8 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.1 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 7.1 | High | CNA (vulncheck.com) |
Official 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Server-Side Request Forgery
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
How developers prevent this class of flaw
- If there is a known list of applications, IP, hostname, and/or domains to which the product is allowed to communicate, then use allowlists to ensure that outgoing requests are restricted to these known entities. The allowlists could be in the application code or possibly enforced by firewalls or network segmentation.
- If the product is expected to be able to connect to arbitrary IP addresses or domains, consider using a denylist that includes private network addresses, internal domain names, etc. The denylist could be in the application code or possibly enforced by firewalls or network segmentation.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in AzuraCast
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
- 8.0 High severity
- 8.8 High severity
- 8.8 High severity
Recent Server-Side Request Forgery vulnerabilities
- 7.6 High severity
- 8.2 High severity
- 7.1 High severity
- 7.7 High severity
- 7.1 High severity
- 7.6 High severity
Spotted an error? Tell us.