Pith Number

pith:IFMVKYUV

pith:2026:IFMVKYUVDSBEUSCO6GW2YVUWJD

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Beyond Pattern Matching: Seven Cross-Domain Techniques for Prompt Injection Detection

Thamilvendhan Munirathinam

Seven techniques borrowed from bioinformatics, linguistics, and other fields detect prompt injections more effectively than regex or classifiers.

arxiv:2604.18248 v2 · 2026-04-20 · cs.CR · cs.CL

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\usepackage{pith}
\pithnumber{IFMVKYUVDSBEUSCO6GW2YVUWJD}

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Record completeness

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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.

Claims

C1strongest claim

The local-alignment detector lifts F1 on deepset from 0.033 to 0.378 with zero additional false positives. The stylometric detector adds 11.1 percentage points of F1 on an indirect-injection benchmark.

C2weakest assumption

That mechanisms proven in their original domains (sequence alignment, fatigue analysis, etc.) will transfer to LLM prompt injection without being bypassed by adaptive adversaries or introducing new failure modes not captured in the six evaluation datasets.

C3one line summary

Seven cross-domain techniques for prompt injection detection are proposed; three implemented versions raise F1 scores on multiple benchmarks while releasing all code and data.

Receipt and verification

First computed	2026-05-20T00:05:44.845693Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

41595562951c824a484ef1adac569648fc63092c2099d1355cd59c24408cc4f1

Aliases

arxiv: 2604.18248 · arxiv_version: 2604.18248v2 · doi: 10.48550/arxiv.2604.18248 · pith_short_12: IFMVKYUVDSBE · pith_short_16: IFMVKYUVDSBEUSCO · pith_short_8: IFMVKYUV

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/IFMVKYUVDSBEUSCO6GW2YVUWJD \
  | 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: 41595562951c824a484ef1adac569648fc63092c2099d1355cd59c24408cc4f1

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "65072f82d2b9aac8b5d15547c412646aa1df0076e9143dc99c9a04008da479fd",
    "cross_cats_sorted": [
      "cs.CL"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "cs.CR",
    "submitted_at": "2026-04-20T13:27:05Z",
    "title_canon_sha256": "22ee573876f9c2fc734740f96a98698e5de844d0d13b190286e8cbf7950ed3d5"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2604.18248",
    "kind": "arxiv",
    "version": 2
  }
}