Serverless, which refers to serverless
computing, is a type of cloud computing execution model in which it is the
responsibility of the cloud provider to execute a piece of code through dynamic
allocation of resources. In it, machine resources are allocated by the cloud
provider, as per demand. Additionally, in it, servers are taken care of on
customers’ behalf and the billing is based on the amount of resources that are
used to run codes, which are run inside stateless containers. These are
triggered by various events, such as database events, HTTP requests, monitoring
alerts, queuing services, file uploads,
cron jobs etc. The code that has to be executed, and which is sent to the cloud
provider for this purpose, is usually a function. This is the reason why
serverless is often referred to as FaaS ( Function as a Service). Resources are
not held in volatile memory in serverless. When any app is not being used, it
does not receive any computing resources.
The term “serverless” is a misnomer because
servers are used in it for executing code for developers by cloud service
providers. Serverless computing is useful as it simplifies the process involved
in the deployment of code into production. The code that is deployed in serverless
can be used with traditionally deployed code, which includes monoliths or
microservices. It is also possible to write applications to be totally
serverless, wherein no provisioned servers are used.
To digress, servers are used by web hosting
companies as well. Web hosting companies use servers to store the files of
websites. These files are delivered over the Internet to render websites
accessible. The most reliable web hosting service providers are usually
referred to as the “Best Website Hosting
Company”, the “Best
Windows Hosting Company”, the “Best Cloud Hosting
Company” etc.
Serverless models are made available by cloud
providers as two distinct services, which are, Function as a Service(FaaS) and
Backend as a Service (BaaS). Serverless offers many benefits, which include
enhanced scalability along with more flexibility, cost reduction, quicker time
to release etc. Additionally, it does away with the need to purchase, provision
and manage backend servers.
In this blog serverless’ security’s in-depth
analysis will be provided, which will touch upon the meaning of serverless
security and the risks involved in it.
Serverless’
Security’s Risks and Challenges
While a serverless model does away with the
worries with regard to infrastructure-related operations, security concerns
remain to be addressed in it. A serverless model requires protection because it
doesn’t use detection system software or firewalls. Moreover, its architecture
neither involves instrumentation agents nor protection methods, such as keys
authentication or file transfer protocols. In serverless architecture, the data
that is requested by any user is stored at the client-side. That is why the
focus remains on data security, behavioral protection, permissions along with
strong code for the purpose of protecting applications against library and
coding risks.
Precautions need to be taken to secure
serverless apps. That is because the serverless architecture makes use of a
smaller approach than microservices. In it miniature, independent pieces of
software are used, which interact through multiple APIs that become public on
interacting with cloud providers. This mechanism leads to the creation of a
security loophole that attackers can use to access the APIs and creates
challenges with regard to the security of serverless apps.
The main security challenges for serverless
have to do with configuration that is insecure, event-data injection, broken
authentication and function permissions.
Additionally, inadequate monitoring of function and logging along with
insecure third party dependencies and insecure storage of application secrets
can be a security challenge for serverless. Let us touch upon each of these
security risks individually.
Multiple features and setting are provided by
cloud service providers. Hence, it is important to ensure that these settings
provide reliable offerings that are authentic. When configurations are not
taken care of, it can lead to risks related to security. Another risk involves
event-data injection. Injection flaws are another type of serious vulnerability
that exists. These take place when input, which is not trustworthy, is
transmitted directly to an interpreter and then gets evaluated or executed. Numerous
event sources are provided by serverless models. These are capable of
triggering a serverless function’s execution. The potential attack surface is
increased by such a huge set of event sources. This leads to the introduction
of complexities with regard to the protection of serverless functions against
event-data injections. Another challenge to serverless’ security are the risks
related to function permissions. There are numerous independent functions in
the serverless ecosystem. Each of these functions is responsible for a certain
task. This interaction among functions might lead to functions becoming overprivileged
with regard to permissions.
Broken authentication presents another
security challenge for serverless. The microservice- like system design of
serverless applications usually contains many distinct serverless functions
that have their own purposes. Public web APIs might be exposed by some of
these. It is important to implement powerful authentication schemes that ensure
access control and protect all the relevant functions along with event type and
trigger.
Inadequate monitoring of function and logging
can be risky for serverless’ security. In the context of serverless’ security,
it is essential to monitor and log events that are related to security in
real-time. This aids in detecting malicious activities and in taking proper
action to thwart those. It aids in averting cyber breaches in real-time. In
serverless architecture, the monitoring and logging aspects exist in a cloud
environment. Serverless architecture vendors usually provide very efficient
logging facilities but these are not capable of ensuring a full security even
audit trail in their basic configuration.
Third party dependencies that are not secure
can be a risk to serverless’ security. A serverless function is supposed to be
a tiny piece of code, which carries out a single discrete task. Often, for
carrying out such a task, the serverless function needs to rely on open source
libraries and third party software. These third party dependencies can render
serverless applications vulnerable to cyber attacks. Insecure storage of
application secrets is another potential threat to the security of serverless.
In this day and age applications are growing in both, scale as well as
complexity. Hence, it becomes extremely crucial to store and maintain properly
application secrets, which include database credentials, API keys and
encryption keys along with the settings for sensitive configuration. A common
mistake, which causes security risks, has to do with the storage of application
secrets within configuration files or database configurations in the form of
plain text. This enables any user to gain access to these, if the user has
“Read” permission. Environmental variables are used for data across the
executions of serverless function. There
is always risk associated with such variables as data can be leaked by these to
unauthorized entities. These are some of the main security risks for serverless
that need to be addressed adequately to ensure the security of serverless.
Source: https://www.htshosting.org/knowledge-base/website-security/107/serverless-security-risks