geedge.lantern.io
detection confidence: medium public

handingkang/fakedns6 implements DNS response spoofing over IPv6, with source under a "ucr.edu" path and a "saddns" binary referencing the academic SAD DNS (Side-channel AttackeD DNS) cache-poisoning technique — evidence MESA Lab is testing/porting the SAD DNS off-path cache-poisoning attack for IPv6, extending classic DNS injection beyond IPv4.

src/ucr.edu/fakedns6/attack.go, saddns, txid.bin
capabilityactive-probing-impl

extracted_by: claude-sonnet-5 · added 2026-08-26 · id: 2026-fakedns6-ipv6-saddns

Related findings

detection

A user manual for a 'Malicious Service IPv6 Address Discovery and Assessment System' documents a sapp application-layer plugin (ipv6_domain.c) that extracts the HTTP Host header, TLS SNI, and DNS AAAA-record domain from live traffic and matches them against a malicious/blocked-domain list to resolve each hit's IPv6 address, alongside a separate active-probing pipeline (ZMapv6 + Entropy/IP-based address-space generation) used to discover IPv6 DNS resolvers and malicious-site IPv6 presence at internet scale.

deployment

A 2020 MESA Lab monthly report describes building an encrypted-DNS gateway device and a self-hosted DoH server that was wired directly into a live "TSG platform WAN net interface", alongside a passive DoH-service-discovery pipeline that found 39 new DoH-serving domains in a single day of backbone ("科技网") traffic; a related note documents actively probing known DoH-serving IPs' upstream resolvers via a proxy network across 196 countries to check which still function.

detection

This CoreDNS-fork DNS server was built by a MESA Lab/IIE engineer (name/email redacted) that bundles a "prober" active-probing plugin, a "v64dns" module, and an "atk" plugin with dedicated branches (atk_DDoS, atk_DDoS_resolver, atk_qp) implementing DNS response amplification and an attempted DNS injection/tampering feature ("注入篡改功能实现尝试"). This combines active DNS probing with resolver-based amplification/attack tooling in one codebase.

detection

A MESA Lab repo (shihaoyue/yy_deploy_script) contains an organized suite of active attack tooling specifically targeting encrypted DNS: DoH/DoT downgrade attacks, DoH/DoT DDoS including a CVE-2024-4487 (HTTP/2 Rapid Reset) exploit script, IPv6 DNS response spoofing/injection (fakedns6 using forged-source-address "saddns"), a DNSSEC-downgrade proxy, DNSSEC-DDoS tooling, and an active DNS-fingerprinting probe pair (fpdns_client/fpdns_server under a folder named "TargetGZ"). This is direct evidence of GFW-adjacent R&D that specifically attacks the encrypted-DNS protocols (DoH/DoT) circumvention tools often rely on for resolver privacy.

detection

An internal MESA Lab presentation by a MESA Lab researcher (name/email redacted) describes 'CartoDNS', a global active/passive encrypted-DNS reconnaissance system that uses DNS-watermark injection across multi-region probing nodes to map DoT/DoH/DoQ resolver topology; as of the presentation it had discovered 80,000+ DoT, 20,000+ DoH and 4,000+ DoQ IPv4 resolvers (plus 1,100+ DoT and 500+ DoH over IPv6) and cataloged 500+ service providers with concrete IP ranges (Cloudflare, Google, Quad9, AdGuard, 360, Alibaba, Tencent, etc.), running continuously since December 2021.

detection

An internal TSG functional-requirements spec ('加密协议JG') defines device support for identifying and blocking ECH, ESNI and QUIC traffic via per-connection SNI/region-matching tables (e.g. DF_QUIC_REGION), plus a companion 'FD报文全流程感知' feature that both passively monitors and actively injects synthetic verification traffic end-to-end through the network path to compute a live per-rule 'CT率' (breakthrough/penetration rate) — the system self-measures how often its own QUIC/ESNI/ECH blocks fail to take effect, and separately throttles logging/blocking detail for rule IDs receiving unusually high hit counts (DF_ATTACK_PROTECTION, 'targeted attack detection').