mcp-server-semgrep/semgrep-rules/ruby/rails/security/audit/avoid-session-manipulation.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: avoid-session-manipulation
  metadata:
    shortDescription: Allowing an attacker to manipulate the session may lead to unintended behavior.
    tags: [security]
    owasp:
    - A01:2021 - Broken Access Control
    cwe:
    - 'CWE-276: Incorrect Default Permissions'
    references:
    - https://brakemanscanner.org/docs/warning_types/session_manipulation/
    category: security
    technology:
    - rails
    help: |
      ## Remediation
      Session manipulation can occur when an application allows user-input in session keys. Since sessions are typically considered a source of truth (e.g. to check the logged-in user or to match CSRF tokens), allowing an attacker to manipulate the session may lead to unintended behavior.

      ## References
      [Session Manipulation](https://brakemanscanner.org/docs/warning_types/session_manipulation/)
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - vuln
    likelihood: MEDIUM
    impact: MEDIUM
    confidence: MEDIUM
  message: >-
    This gets data from session using user inputs. A malicious user may be able to retrieve
    information from your session that you didn't intend them to. Do not use user input as
    a session key.
  languages: [ruby]
  severity: WARNING
  mode: taint
  pattern-sources:
  - pattern: params
  - pattern: cookies
  - pattern: request.env
  pattern-sinks:
  - pattern: session[...]