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 nld. Inferred improvements during Apr 2026: ASN Name Fixed-By 134835 SNL-HK 2026-04-11 Further information for the inferred remediation is available at: https://spoofer.caida.org/remedy.php Source Address Validation issues inferred during Apr 2026: ASN Name First-Spoofed Last-Spoofed 28685 ASN-ROUTIT 2017-03-26 2026-04-30 1136 KPN 2019-09-04 2026-04-22 3920 IMS-RTFM 2023-10-06 2026-04-24 35316 PRODACOM 2025-12-17 2026-04-29 60781 LEASEWEB-NL-AMS-01 2026-02-08 2026-04-26 906 2026-03-14 2026-04-25 32519 DMITI-SERVICES 2026-03-28 2026-04-25 6206 PARK-3 2026-04-30 2026-04-30 Further information for these tests where we received spoofed packets is available at: https://spoofer.caida.org/recent_tests.php?country_include=nld&no_block=1 Please send any feedback or suggestions to spoofer-info@caida.org