go.lang.security.audit.unsafe.use-of-unsafe-block

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Using the unsafe package in Go gives you low-level memory management and many of the strengths of the C language, but also steps around the type safety of Go and can lead to buffer overflows and possible arbitrary code execution by an attacker. Only use this package if you absolutely know what you're doing.

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Defintion

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rules:
  - id: use-of-unsafe-block
    message: Using the unsafe package in Go gives you low-level memory management
      and many of the strengths of the C language, but also steps around the
      type safety of Go and can lead to buffer overflows and possible arbitrary
      code execution by an attacker. Only use this package if you absolutely
      know what you're doing.
    languages:
      - go
    severity: WARNING
    metadata:
      cwe:
        - "CWE-242: Use of Inherently Dangerous Function"
      source_rule_url: https://github.com/securego/gosec/blob/master/rules/unsafe.go
      category: security
      technology:
        - go
      confidence: LOW
      references:
        - https://cwe.mitre.org/data/definitions/242.html
      subcategory:
        - audit
      likelihood: LOW
      impact: LOW
      license: Commons Clause License Condition v1.0[LGPL-2.1-only]
      vulnerability_class:
        - Dangerous Method or Function
    pattern: unsafe.$FUNC(...)

Examples

unsafe.go

package main

import (
	"fmt"
	"unsafe"

	foobarbaz "unsafe"
)

type Fake struct{}

func (Fake) Good() {}
func main() {
	unsafeM := Fake{}
	unsafeM.Good()
	intArray := [...]int{1, 2}
	fmt.Printf("\nintArray: %v\n", intArray)
	intPtr := &intArray[0]
	fmt.Printf("\nintPtr=%p, *intPtr=%d.\n", intPtr, *intPtr)
	// ruleid: use-of-unsafe-block
	addressHolder := uintptr(foobarbaz.Pointer(intPtr)) + unsafe.Sizeof(intArray[0])
	// ruleid: use-of-unsafe-block
	intPtr = (*int)(foobarbaz.Pointer(addressHolder))
	fmt.Printf("\nintPtr=%p, *intPtr=%d.\n\n", intPtr, *intPtr)
}