go.lang.security.bad_tmp.bad-tmp-file-creation

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File creation in shared tmp directory without using ioutil.Tempfile

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Defintion

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rules:
  - id: bad-tmp-file-creation
    message: File creation in shared tmp directory without using ioutil.Tempfile
    languages:
      - go
    severity: WARNING
    metadata:
      cwe:
        - "CWE-377: Insecure Temporary File"
      source-rule-url: https://github.com/securego/gosec
      category: security
      technology:
        - go
      confidence: LOW
      owasp:
        - A01:2021 - Broken Access Control
      references:
        - https://owasp.org/Top10/A01_2021-Broken_Access_Control
      subcategory:
        - audit
      likelihood: LOW
      impact: LOW
      license: Commons Clause License Condition v1.0[LGPL-2.1-only]
    pattern-either:
      - pattern: ioutil.WriteFile("=~//tmp/.*$/", ...)
      - pattern: os.Create("=~//tmp/.*$/", ...)

Examples

bad_tmp.go

package samples

import (
	"fmt"
	"io/ioutil"
)

func main() {
	// ruleid:bad-tmp-file-creation
	err := ioutil.WriteFile("/tmp/demo2", []byte("This is some data"), 0644)
	if err != nil {
		fmt.Println("Error while writing!")
	}
}
func main_good() {
	// ok:bad-tmp-file-creation
	err := ioutil.Tempfile("/tmp", "my_temp")
	if err != nil {
		fmt.Println("Error while writing!")
	}
}