Flawfinder version 2.0.10, (C) 2001-2019 David A. Wheeler.
Number of rules (primarily dangerous function names) in C/C++ ruleset: 223
Examining data/xssproxy-1.0.0/xssproxy.c

FINAL RESULTS:

data/xssproxy-1.0.0/xssproxy.c:40:5:  [4] (format) vfprintf:
  If format strings can be influenced by an attacker, they can be exploited
  (CWE-134). Use a constant for the format specification.
    vfprintf(stdout, format, args);

ANALYSIS SUMMARY:

Hits = 1
Lines analyzed = 319 in approximately 0.02 seconds (18902 lines/second)
Physical Source Lines of Code (SLOC) = 267
Hits@level = [0]   4 [1]   0 [2]   0 [3]   0 [4]   1 [5]   0
Hits@level+ = [0+]   5 [1+]   1 [2+]   1 [3+]   1 [4+]   1 [5+]   0
Hits/KSLOC@level+ = [0+] 18.7266 [1+] 3.74532 [2+] 3.74532 [3+] 3.74532 [4+] 3.74532 [5+]   0
Dot directories skipped = 1 (--followdotdir overrides)
Minimum risk level = 1
Not every hit is necessarily a security vulnerability.
There may be other security vulnerabilities; review your code!
See 'Secure Programming HOWTO'
(https://dwheeler.com/secure-programs) for more information.