Skip to content

Latest commit

 

History

History
73 lines (54 loc) · 6.52 KB

mitigations.md

File metadata and controls

73 lines (54 loc) · 6.52 KB

Mitigation Strategies Analysis for spf13/cobra

Mitigation Strategy: Strategic Command and Flag Naming

Description:

  1. Choose Descriptive Names: When defining commands and flags using cobra.Command and its associated methods (e.g., Flags().StringVarP(), AddCommand()), select names that are clear, unambiguous, and unlikely to be mistyped.
  2. Avoid Short Aliases (Generally): While Cobra allows short aliases (e.g., -h for --help), minimize their use, especially for critical commands. If used, ensure they are extremely well-known and documented.
  3. Consistent Casing: Establish and enforce a consistent casing convention (kebab-case, snake_case) for command and flag names within your Cobra setup.
  4. Review Existing Cobra Definitions: Examine your cmd package (or wherever your Cobra commands are defined) and refactor any command or flag names that are ambiguous or prone to typosquatting.

Threats Mitigated:

  • Unexpected Command Execution (Typosquatting): (Severity: Medium) - Reduces the chance of a user accidentally running the wrong command due to a typo, especially if a similarly named command exists.

Impact:

  • Unexpected Command Execution: Risk reduced from Medium to Low.

Currently Implemented:

  • Example: A general guideline to use descriptive names exists, but it's not consistently followed in the cmd package.

Missing Implementation:

  • Example: Short, ambiguous command names exist (e.g., cmd/r.go, cmd/s.go). These should be renamed to be more descriptive.
  • Example: Inconsistent casing is used across different command files (e.g., cmd/addUser.go vs. cmd/delete-user.go).

Mitigation Strategy: Cobra Configuration and Feature Control

Description:

  1. DisableFlagParsing = true (If Applicable): If a command does not use flags, explicitly disable flag parsing by setting DisableFlagParsing: true on the cobra.Command instance. This prevents Cobra from attempting to process any flags, reducing the attack surface.
  2. TraverseChildren = false (Carefully): By default, Cobra's TraverseChildren is true, meaning it continues to parse flags after finding a valid subcommand. If this behavior is not needed, set TraverseChildren: false on the relevant cobra.Command to limit flag parsing. Understand the implications before changing this.
  3. DisableSuggestions = true (If High Risk): If the risk of accidental command execution via typos is high (especially for destructive commands), disable Cobra's command suggestion feature by setting DisableSuggestions: true on the root command. Alternatively, customize the suggestion behavior if possible.
  4. PersistentFlags Review: Carefully review the use of PersistentFlags(). These flags are inherited by all subcommands. Ensure that persistent flags do not inadvertently expose sensitive functionality or information to subcommands that should not have access. Use them sparingly and only when truly necessary.
  5. ValidArgs and ValidArgsFunction: Use ValidArgs to define a static list of allowed arguments for a command, or ValidArgsFunction for dynamic validation. This provides built-in input validation at the Cobra level.
  6. Args: Use the Args field on cobra.Command to specify a validator function for positional arguments. Cobra provides several built-in validators like cobra.MinimumNArgs(n), cobra.MaximumNArgs(n), cobra.ExactArgs(n), cobra.NoArgs, cobra.OnlyValidArgs. Use these or define a custom validator.

Threats Mitigated:

  • Unexpected Command Execution (Misconfiguration): (Severity: Medium) - By controlling how Cobra parses commands and flags.
  • Denial of Service (via Flags): (Severity: High) - By disabling flag parsing where it's not needed.
  • Information Disclosure (via Suggestions): (Severity: Low) - By disabling or customizing suggestions.

Impact:

  • Unexpected Command Execution: Risk reduced from Medium to Low.
  • Denial of Service: Risk reduced from High to Medium (in specific scenarios where flags are a vector).
  • Information Disclosure: Risk reduced from Low to Very Low.

Currently Implemented:

  • Example: DisableSuggestions is set to true on the root command in cmd/root.go.

Missing Implementation:

  • Example: TraverseChildren is not explicitly set on any commands, relying on the default behavior. This should be reviewed and potentially set to false where appropriate.
  • Example: Persistent flags are used in cmd/root.go without a clear understanding of their impact on subcommands.
  • Example: ValidArgs and Args validators are not used, relying solely on custom validation logic after Cobra parsing.

Mitigation Strategy: Customizing Help Text via Cobra

Description:

  1. Short, Long, Example Fields: Use the Short, Long, and Example fields of the cobra.Command struct to provide clear, concise, and security-conscious descriptions of each command and its flags.
  2. Avoid Sensitive Information: Do not include any information in the help text that could be useful to an attacker (e.g., internal file paths, specific library versions, API keys).
  3. Review Generated Help: Regularly run your-app help and review the output to ensure that the help text is accurate, helpful, and does not reveal any sensitive information.
  4. Customize Flag Help: Use the Usage field of flags (e.g., Flags().StringVarP(&myVar, "myflag", "m", "", "A secure description of myflag")) to provide specific, secure descriptions for each flag.

Threats Mitigated:

  • Information Disclosure: (Severity: Low to Medium) - Prevents the leakage of sensitive information through Cobra's automatically generated help text.

Impact:

  • Information Disclosure: Risk reduced from Low/Medium to Very Low.

Currently Implemented:

  • Example: Basic Short descriptions are provided for some commands in the cmd package.

Missing Implementation:

  • Example: The Long and Example fields are not consistently used, resulting in incomplete or unhelpful help text for many commands.
  • Example: No systematic review of the generated help text has been performed to check for sensitive information disclosure.
  • Example: Flag Usage fields are not customized, relying on default descriptions.