Pith Number

pith:XU3DRKJ3

pith:2026:XU3DRKJ33V7UUADZJRSAQGLLFD

not attested not anchored not stored refs pending

When the Aggregator Cheats: Data-Free Backdoors in Federated LLM-based QA Systems

Chenqing Zhu, Qingming Li, Songze Li, Yanbo Dai, Yulong Tian

arxiv:2606.27511 v1 · 2026-06-25 · cs.CR

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{XU3DRKJ33V7UUADZJRSAQGLLFD}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-06-29T00:14:08.634738Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

bd3638a93bdd7f4a00794c6408196b28e0bddfdfefbc0e1aa619b3f119598216

Aliases

arxiv: 2606.27511 · arxiv_version: 2606.27511v1 · doi: 10.48550/arxiv.2606.27511 · pith_short_12: XU3DRKJ33V7U · pith_short_16: XU3DRKJ33V7UUADZ · pith_short_8: XU3DRKJ3

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/XU3DRKJ33V7UUADZJRSAQGLLFD \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: bd3638a93bdd7f4a00794c6408196b28e0bddfdfefbc0e1aa619b3f119598216

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "39d02f71ccc596217b43a7963239ed58973b6df520d1b4da4d998502a1d2e778",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.CR",
    "submitted_at": "2026-06-25T19:53:37Z",
    "title_canon_sha256": "929843a56f00a4b7c07640154e043284b1f20599468bde968aff519da05379e0"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2606.27511",
    "kind": "arxiv",
    "version": 1
  }
}