In response to feedback from operational security communities, CAIDA's source address validation measurement project (https://spoofer.caida.org) is automatically generating monthly reports of ASes originating prefixes in BGP for systems from which we received packets with a spoofed source address. We are publishing these reports to network and security operations lists in order to ensure this information reaches operational contacts in these ASes. This report summarises tests conducted within usa, can. Inferred improvements during Aug 2021: ASN Name Fixed-By 212000 2021-08-01 208188 PUGET-SOUND-NETWORKS 2021-08-04 40676 AS40676 2021-08-04 19531 NODESDIRECT 2021-08-29 Further information for the inferred remediation is available at: https://spoofer.caida.org/remedy.php Source Address Validation issues inferred during Aug 2021: ASN Name First-Spoofed Last-Spoofed 6939 HURRICANE 2016-02-22 2021-08-31 577 BACOM 2016-03-09 2021-08-30 209 CENTURYLINK-US-LEGACY-QWEST 2016-08-16 2021-08-25 6128 CABLE-NET-1 2016-09-03 2021-08-15 20412 CLARITY-TELECOM 2016-09-30 2021-08-31 6181 FUSE-NET 2016-10-10 2021-08-29 11427 TWC-11427-TEXAS 2016-10-21 2021-08-27 1403 EBOX 2016-11-12 2021-08-19 22898 ATLINK 2016-12-16 2021-08-30 701 UUNET 2017-06-14 2021-08-27 63296 AWBROADBAND 2017-09-01 2021-08-27 23089 HOTWIRE-COMMUNICATIONS 2017-09-30 2021-08-31 12222 AKAMAI 2018-02-14 2021-08-11 393564 SPOKANE 2018-06-05 2021-08-24 33452 RW 2018-09-19 2021-08-24 5078 ONENET-AS-1 2020-04-06 2021-08-28 11525 HRTC 2020-06-27 2021-08-26 56207 Converge 2021-03-26 2021-08-27 13876 FIBER-64 2021-05-20 2021-08-28 2900 WN-AZ 2021-08-24 2021-08-24 8038 6CONNECT 2021-08-30 2021-08-30 Further information for these tests where we received spoofed packets is available at: https://spoofer.caida.org/recent_tests.php?country_include=usa,can&no_block=1 Please send any feedback or suggestions to spoofer-info@caida.org