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Operating systems have global directories where any user has write access. Those folders are mostly used as temporary storage areas like
/tmp in Linux based systems. An application manipulating files from these folders is exposed to race conditions on filenames: a malicious
user can try to create a file with a predictable name before the application does. A successful attack can result in other files being accessed,
modified, corrupted or deleted. This risk is even higher if the application runs with elevated permissions.
In the past, it has led to the following vulnerabilities:

   CVE-2012-2451 
   CVE-2015-1838 

This rule raises an issue whenever it detects a hard-coded path to a publicly writable directory like /tmp (see examples bellow). It
also detects access to environment variables that point to publicly writable directories, e.g., TMP and TMPDIR.

   /tmp 
   /var/tmp 
   /usr/tmp 
   /dev/shm 
   /dev/mqueue 
   /run/lock 
   /var/run/lock 
   /Library/Caches 
   /Users/Shared 
   /private/tmp 
   /private/var/tmp 
   \Windows\Temp 
   \Temp 
   \TMP 

Ask Yourself Whether

   Files are read from or written into a publicly writable folder 
   The application creates files with predictable names into a publicly writable folder 

There is a risk if you answered yes to any of those questions.
Recommended Secure Coding Practices

   Use a dedicated sub-folder with tightly controlled permissions 
   Use secure-by-design APIs to create temporary files. Such API will make sure:
    
       The generated filename is unpredictable 
       The file is readable and writable only by the creating user ID 
       The file descriptor is not inherited by child processes 
       The file will be destroyed as soon as it is closed 
    
  

Sensitive Code Example
file = open("/tmp/temporary_file","w+") # Sensitive

tmp_dir = os.environ.get('TMPDIR') # Sensitive
file = open(tmp_dir+"/temporary_file","w+")

Compliant Solution
import tempfile

file = tempfile.TemporaryFile(dir="/tmp/my_subdirectory", mode='"w+") # Compliant

See

   OWASP - Top 10 2021 Category A1 - Broken Access Control 
   OWASP - Top 10 2017 Category A5 - Broken Access Control
  
   OWASP - Top 10 2017 Category A3 - Sensitive Data
  Exposure 
   CWE - CWE-377 - Insecure Temporary File 
   CWE - CWE-379 - Creation of Temporary File in Directory with Incorrect Permissions
  
   OWASP, Insecure Temporary File 
   Python tempfile module 
   STIG Viewer - Application Security and
  Development: V-222567 - The application must not be vulnerable to race conditions.