Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.
Comment: Edited by sciSpider Java v3.0

...

Code Block
bgColor#FFcccc
class Format {
  static Calendar c = new GregorianCalendar(1995, GregorianCalendar.MAY, 23);
  public static void main(String[] args) {  
    // args[0] is the credit card expiration date
    // args[0] can contain either %1$tm, %1$te or %1$tY as malicious arguments
    // First argument prints 05 (May), second prints 23 (day) and third prints 1995 (year)
    // Perform comparison with c, if it doesn't match print the following line
    System.out.printf(args[0] + "" did not match! HINT: It was issued on %1$terd of some month"", c);
  }
}

Compliant Solution

...

Code Block
bgColor#ccccff
class Format {
  static Calendar c = new GregorianCalendar(1995, MAY, 23);
  public static void main(String[] args) {  
    // args[0] is the credit card expiration date
    // Perform comparison with c, if it doesn't match print the following line
    System.out.printf(""The input did not match! HINT: It was issued on %1$terd of some month"", c);
  }
}

Risk Assessment

Allowing user input to taint the format string may cause information leaks or denial of service.

...

Search for vulnerabilities resulting from the violation of this rule on the CERT website.

Other Languages

This rule appears in the C Secure Coding Standard as FIO30-C. Exclude user input from format strings.

...

Wiki Markup
\[[API 06|AA. Java References#API 06]\] [Class Formatter|http://java.sun.com/javase/6/docs/api/java/util/Formatter.html]
\[[Seacord 05|AA. Java References#Seacord 05]\] Chapter 6, Formatted Output
\[[MITRE 09|AA. Java References#MITRE 09]\] [CWE ID 674|http://cwe.mitre.org/data/definitions/674.html] ""Uncontrolled Format String""

...

FIO32-J. Ensure all resources are properly closed when they are no longer needed            09. Input Output (FIO)            FIO34-J. Do not create temporary files in shared directories