Vulnerability Spotlight: Further NTPD Vulnerabilities
Summary: Cisco Talos discovered six vulnerabilities in the Network Time Protocol daemon (ntpd) that let attackers craft UDP packets to cause denial of service or prevent correct time from being set. The flaws include a timing side channel in MD5 digest comparison (CVE-2016-1550), implicit trust of reference clock traffic from 127.127.0.0/16 (CVE-2016-1551), a Sybil attack via unlimited peers sharing one key (CVE-2016-1549), spoofed crypto-NAK packets breaking peer associations (CVE-2016-1547), and a forced switch from basic to interleaved mode (CVE-2016-1548).
Key Takeaway: Since 2013 criminals have abused NTP packets for amplified denial of service attacks, and altered time can stop time-dependent services from starting, exhaust system resources, or grant access through expired certificates.
Read the original at Cisco Talos ↗
- Topics
- Vulnerabilities & Patching
- Mentions
- CVE-2016-1550CVE-2016-1551
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