Webhook-url-http-3a-2f-2f169.254.169.254-2fmetadata-2fidentity-2foauth2-2ftoken

If possible, only allow webhooks to be sent to an approved list of known third-party domains.

If you see this string inside a configuration file or a variable named webhook-url , it usually implies one of two scenarios:

– URL encoding bypasses simple string blacklists that look for 169.254.169.254 or metadata . Attackers can also use decimal, octal, or IPv6 representations (e.g., http://[::ffff:169.254.169.254]/ ).

webhook-url-http-3A-2F-2F169.254.169.254-2Fmetadata-2Fidentity-2Foauth2-2Ftoken If possible, only allow webhooks to be sent

: Explicitly block requests to Link-Local addresses (like 169.254.169.254 ) and private IP ranges (RFC 1918).

You must include the header Metadata: true to prevent Server-Side Request Forgery (SSRF) attacks. Required Parameters: api-version : Usually 2018-02-01 or later.

: Webhook functionality is a prime target for SSRF because it inherently expects a URL and triggers the server to make an outbound request. Attack Step webhook-url-http-3A-2F-2F169

: A VM makes an HTTP request to the metadata service endpoint to request an OAuth2 token. The request typically includes parameters like the resource (or audience) for which the token is being requested.

A webhook URL, also known as a callback URL or webhook endpoint, is a URL that an application or service uses to send notifications or updates to another application or service. It's essentially a callback function that receives data from a server.

This URL is not an ordinary web endpoint. It represents a targeted attempt by an attacker to exploit an application's webhook system to compromise internal cloud infrastructure. Deconstructing the Payload : Webhook functionality is a prime target for

http://169.254.169.254/metadata/identity/oauth2/token

User-controlled URL input. The app accepts a URL for callbacks, image fetching, import jobs, preview generation, etc. Server perfo... Narendar Battula (nArEn)