A vulnerability in the Transaction Language 1 (TL1) code of Cisco ASR 900 Series routers could allow an unauthenticated, remote attacker to cause a reload of, or remotely execute code on, the affected system. This vulnerability affects Cisco ASR 900 Series Aggregation Services Routers (ASR902, ASR903, and ASR907) that are running the following releases of Cisco IOS XE Software: 3.17.0S 3.17.1S 3.17.2S 3.18.0S 3.18.1S. More Information: CSCuy15175. Known Affected Releases: 15.6(1)S 15.6(2)S. Known Fixed Releases: 15.6(1)S2.12 15.6(1.17)S0.41 15.6(1.17)SP 15.6(2)SP 16.4(0.183) 16.5(0.10).