An issue was discovered in Suricata 4.1.x before 4.1.4. If the input of the function SSHParseBanner is composed only of a \n character, then the program runs into a heap-based buffer over-read. This occurs because the erroneous search for \r results in an integer underflow.

References

• https://nvd.nist.gov/vuln/detail/CVE-2019-10053
• https://lists.openinfosecfoundation.org/pipermail/oisf-announce/
• https://suricata-ids.org/2019/04/30/suricata-4-1-4-released/