### [CVE-2015-1798](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1798) ![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue) ![](https://img.shields.io/static/v1?label=Version&message=%3D%20n%2Fa%20&color=brighgreen) ![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen) ### Description The symmetric-key feature in the receive function in ntp_proto.c in ntpd in NTP 4.x before 4.2.8p2 requires a correct MAC only if the MAC field has a nonzero length, which makes it easier for man-in-the-middle attackers to spoof packets by omitting the MAC. ### POC #### Reference - http://www.kb.cert.org/vuls/id/374268 - http://www.oracle.com/technetwork/topics/security/bulletinapr2015-2511959.html - http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html #### Github No PoCs found on GitHub currently.