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 Jul 2023: ASN Name Fixed-By 54825 PACKET 2023-07-02 6128 CABLE-NET-1 2023-07-03 6124 MARIST 2023-07-06 14576 HOSTING-SOLUTIONS 2023-07-16 394233 CLOUDWIFI 2023-07-21 Further information for the inferred remediation is available at: https://spoofer.caida.org/remedy.php Source Address Validation issues inferred during Jul 2023: ASN Name First-Spoofed Last-Spoofed 3356 LEVEL3 2016-03-06 2023-07-14 209 CENTURYLINK-US-LEGACY-QWEST 2016-08-16 2023-07-27 20412 CLARITY-TELECOM 2016-09-30 2023-07-31 25787 ROWE-NETWORKS 2016-10-21 2023-07-28 11427 TWC-11427-TEXAS 2016-10-21 2023-07-25 10796 TWC-10796-MIDWEST 2016-10-24 2023-07-30 271 BCNET 2016-10-24 2023-07-29 852 ASN852 2017-04-16 2023-07-31 53274 3DB-WIRELESS 2019-01-18 2023-07-05 46997 2021-12-22 2023-07-27 394414 E2WS 2022-05-08 2023-07-26 397086 GLOBAL-FRAG-NETWORKS-HOUSTON 2022-06-16 2023-07-25 400517 2022-10-03 2023-07-10 12183 TALKIE-COMMUNICATIONS 2022-12-10 2023-07-21 964 GONET-ASN-17 2023-03-15 2023-07-07 41378 KirinoNET 2023-03-23 2023-07-28 3701 NERONET 2023-04-18 2023-07-26 400282 2023-04-27 2023-07-28 13693 NTS-ONLINE 2023-05-05 2023-07-29 46690 SNET-FCC 2023-05-20 2023-07-29 200063 CAMINI-IMPEX 2023-06-16 2023-07-21 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