services / Azure / Private DNS MX record set

An MX (mail-exchange) record set within an Azure Private DNS zone, which directs internal mail-routing name resolution for resources within linked virtual networks.

Private DNS zones serve name resolution for a single network function; reading records is reconnaissance while writing/deleting can redirect or break internal resolution.

Microsoft.​Network/​privateDnsZones/​MX/​write

Creating/replacing MX records overwrites internal mail routing, letting an attacker redirect mail flow to attacker-controlled hosts and arbitrarily route that name within the private zone.

Risks

1. Domain takeover (CRITICAL)
2. Data manipulation (HIGH)

Scope: HIGH

This privilege may grant access to sensitive data from a single organizational function, or allow interruption of a service supporting a single organizational function.

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