Mitigation Strategy: Environment Input Validation and Sanitization (Gym-Specific Aspects)
-
Description:
gym.spaces
Definition: Usegym.spaces
(e.g.,Discrete
,Box
,Tuple
,Dict
) to strictly define the action and observation spaces of your environment. This is fundamental to howgym
environments are structured.step()
Function Validation: Within the environment'sstep()
function (the core interaction point), rigorously validate theaction
received from the agent against the definedaction_space
. Useself.action_space.contains(action)
to check if the action is valid. Raise aTypeError
or a custom exception if it's not.- Observation Space Consistency: Ensure that the observations returned by the
step()
andreset()
functions always conform to the definedobservation_space
. Useself.observation_space.contains(observation)
for verification before returning the observation. - Reward Type Checking: Enforce that the reward returned by
step()
is of the expected type (usually a float). done
andinfo
Handling: Ensure thedone
signal (boolean) and theinfo
dictionary (if used) are correctly formatted and do not leak sensitive information.
-
Threats Mitigated:
- Environment Code Injection (Severity: High): By strictly enforcing the
gym.spaces
contract, you prevent the agent from sending arbitrary data that could exploit vulnerabilities in the environment's internal logic. - Environment Logic Errors (Severity: Medium): Reduces the chance of unexpected behavior or crashes due to invalid actions or observations.
- Information Disclosure (Severity: Low): Proper handling of the
info
dictionary prevents leaking internal environment details.
- Environment Code Injection (Severity: High): By strictly enforcing the
-
Impact:
- Environment Code Injection: Risk significantly reduced (from High to Low).
- Environment Logic Errors: Risk reduced (from Medium to Low).
- Information Disclosure: Risk reduced (from Low to Negligible).
-
Currently Implemented: Partially.
gym.spaces
are defined, but thecontains()
checks are not consistently used in all environment implementations. Reward type checking is inconsistent. -
Missing Implementation: Consistent use of
self.action_space.contains(action)
andself.observation_space.contains(observation)
in all environmentstep()
andreset()
methods. Consistent reward type checking. Review ofinfo
dictionary usage for potential information leaks.
Mitigation Strategy: Environment Wrapper Usage (Gym's Wrapper
Class)
-
Description:
- Identify Wrapper Needs: Determine if any standard
gym.wrappers
(or custom wrappers) can enhance security. Examples include:gym.wrappers.ClipAction
: Clips actions to the valid range defined by theaction_space
.gym.wrappers.RescaleAction
: Rescales actions from one range to another.gym.wrappers.TimeLimit
: Limits the maximum number of steps per episode.gym.wrappers.NormalizeObservation
andgym.wrappers.NormalizeReward
: Normalize observations and rewards, which can improve training stability and, indirectly, security by reducing the likelihood of numerical issues.
- Implement Wrappers: Wrap your environment using the appropriate
gym.Wrapper
classes. For example:env = gym.wrappers.ClipAction(env)
. - Custom Wrappers: If necessary, create custom
gym.Wrapper
subclasses to implement specific security checks or transformations. For example, a custom wrapper could log all actions taken by the agent for auditing purposes, or it could add noise to the observations to prevent the agent from overfitting to specific environment details. - Order of Wrappers: Be mindful of the order in which you apply wrappers, as this can affect their behavior.
- Identify Wrapper Needs: Determine if any standard
-
Threats Mitigated:
- Out-of-Bounds Actions (Severity: Medium):
ClipAction
andRescaleAction
prevent the agent from taking actions outside the defined range. - Environment Logic Errors (Severity: Medium): Wrappers can help enforce constraints and prevent unexpected behavior.
- Denial of Service (DoS) (Severity: Medium):
TimeLimit
prevents excessively long episodes. - Overfitting to Environment Details (Severity: Low): Observation/reward normalization can make the agent less sensitive to specific environment quirks.
- Out-of-Bounds Actions (Severity: Medium):
-
Impact:
- Out-of-Bounds Actions: Risk reduced (from Medium to Low).
- Environment Logic Errors: Risk reduced (from Medium to Low).
- Denial of Service (DoS): Risk reduced (from Medium to Low).
- Overfitting: Risk reduced (from Low to Negligible).
-
Currently Implemented:
TimeLimit
wrapper is used in some environments. -
Missing Implementation:
ClipAction
andRescaleAction
are not consistently used where appropriate. No custom security-focused wrappers are implemented. A systematic review of which wrappers could benefit each environment is needed.
Mitigation Strategy: Using Trusted and Well-Maintained Environments
-
Description:
- Prioritize Official Environments: Whenever possible, use environments from the official OpenAI Gym distribution (e.g., Atari, Classic Control, MuJoCo). These environments are generally well-tested and maintained.
- Vetted Community Environments: If using community-contributed environments (e.g., from
gym-contrib
or other sources), carefully evaluate their source code, documentation, and community reputation. Look for environments that are actively maintained and have a history of addressing security concerns. - Avoid Untrusted Environments: Avoid using environments from unknown or untrusted sources, as they may contain vulnerabilities or malicious code.
- Regularly Check for Updates: Even for trusted environments, regularly check for updates and security patches.
-
Threats Mitigated:
- Vulnerabilities in Environment Code (Severity: Variable, from Low to Critical): Reduces the risk of using environments with known or unknown security flaws.
-
Impact:
- Vulnerabilities in Environment Code: Risk significantly reduced (depending on the source and maintenance of the environment).
-
Currently Implemented: The project primarily uses official OpenAI Gym environments.
-
Missing Implementation: A formal process for vetting and approving any new environments (especially community-contributed ones) is not in place.