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/proftpd-mod-dnsbl-0.1.5/mod_dnsbl.c

FINAL RESULTS:

data/proftpd-mod-dnsbl-0.1.5/mod_dnsbl.c:96:7:  [2] (buffer) memcpy:
  Does not check for buffer overflows when copying to destination (CWE-120).
  Make sure destination can always hold the source data.
      memcpy(&tmp->na_addr.v4.sin_addr,
data/proftpd-mod-dnsbl-0.1.5/mod_dnsbl.c:117:12:  [2] (buffer) char:
  Statically-sized arrays can be improperly restricted, leading to potential
  overflows or other issues (CWE-119!/CWE-120). Perform bounds checking, use
  functions that limit length, or ensure that the size is larger than the
  maximum possible length.
  unsigned char reason[NS_PACKETSZ];
data/proftpd-mod-dnsbl-0.1.5/mod_dnsbl.c:148:9:  [2] (buffer) memcpy:
  Does not check for buffer overflows when copying to destination (CWE-120).
  Make sure destination can always hold the source data.
        memcpy(reject_reason, (unsigned char *) ns_rr_rdata(rr), len);
data/proftpd-mod-dnsbl-0.1.5/mod_dnsbl.c:56:20:  [1] (buffer) strlen:
  Does not handle strings that are not \0-terminated; if given one it may
  perform an over-read (it could cause a crash if unprotected) (CWE-126).
  size_t addrlen = strlen(ip_addr) +1;

ANALYSIS SUMMARY:

Hits = 4
Lines analyzed = 446 in approximately 0.03 seconds (15605 lines/second)
Physical Source Lines of Code (SLOC) = 285
Hits@level = [0]   0 [1]   1 [2]   3 [3]   0 [4]   0 [5]   0
Hits@level+ = [0+]   4 [1+]   4 [2+]   3 [3+]   0 [4+]   0 [5+]   0
Hits/KSLOC@level+ = [0+] 14.0351 [1+] 14.0351 [2+] 10.5263 [3+]   0 [4+]   0 [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.