In most cases, trust boundaries are violated when a secret is exposed in a source code repository or an uncontrolled deployment environment.
Unintended people who don’t need to know the secret might get access to it. They might then be able to use it to gain unwanted access to associated
services or resources.
The trust issue can be more or less severe depending on the people’s role and entitlement.
What is the potential impact?
Below are some real-world scenarios that illustrate some impacts of an attacker exploiting the secret.
Infrastructure takeover
By obtaining a leaked secret, an attacker can gain control over your organization’s Azure App Service infrastructure. They can modify DNS settings,
redirect traffic, or launch malicious instances that can be used for various nefarious activities, including launching DDoS attacks, hosting phishing
websites, or distributing malware. Malicious instances may also be used for resource-intensive tasks such as cryptocurrency mining.
This can result in legal liability, but also increased costs, degraded performance, and potential service disruptions.
Furthermore, corporate Azure App Service infrastructures are often connected to other services and to the internal networks of the organization.
Because of this, cloud infrastructure is often used by attackers as a gateway to other assets. Attackers can leverage this gateway to gain access to
more services, to compromise more business-critical data and to cause more damage to the overall infrastructure.
Compromise of sensitive data
If the affected service is used to store or process personally identifiable information or other sensitive data, attackers knowing an
authentication secret could be able to access it. Depending on the type of data that is compromised, it could lead to privacy violations, identity
theft, financial loss, or other negative outcomes.
In most cases, a company suffering a sensitive data compromise will face a reputational loss when the security issue is publicly disclosed.
Modification of application data
Applications may rely on data that cannot be distributed with the application code. This may be due to the size of the data, or because the data is
regularly updated. This data is downloaded by the application as it is needed.
If an attacker can gain access to an authentication secret, they may be able to alter or delete this application data. This may cause parts of the
application to misbehave or stop working. Maliciously altered data could also contain undesirable content which results in reputational damage.
Malware distribution
Due to this vulnerability, malware can be stored and spread, both to users of the service and to other potential targets.
A malware depends on
the attacker’s intentions, as the following examples show:
- Cryptojacking malware, whose goal is to "mine" cryptocurrencies on the affected computers or servers.
- Spyware that spies out sensitive information from victims.
In the worst case, malware can cause the target systems to be completely compromised and allow attackers to infiltrate the systems.
Financial loss
Financial losses can occur when a secret is used to access a paid third-party-provided service and is disclosed as part of the source code of
client applications. Having the secret, each user of the application will be able to use it without limit to use the third party service to their own
need, including in a way that was not expected.
This additional use of the secret will lead to added costs with the service provider.
Moreover, when rate or volume limiting is set up on the provider side, this additional use can prevent the regular operation of the affected
application. This might result in a partial denial of service for all the application’s users.
