A vulnerability in the IPsec component of Cisco StarOS for Cisco ASR 5000 Series Routers could allow an unauthenticated, remote attacker to terminate all active IPsec VPN tunnels and prevent new tunnels from establishing, resulting in a denial of service (DoS) condition. Affected Products: ASR 5000 Series Routers, Virtualized Packet Core (VPC) Software. More Information: CSCvc21129. Known Affected Releases: 21.1.0 21.1.M0.65601 21.1.v0. Known Fixed Releases: 21.2.A0.65754 21.1.b0.66164 21.1.V0.66014 21.1.R0.65759 21.1.M0.65749 21.1.0.66030 21.1.0.
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170621-asr