earlyink Record 3/270 confirmed · median 3d early
263 first flagged26 Oct 2026

Near Miss: injection tests for answers that stay on task but come out wrong

Test pack that plants subtle instructions in your documents and catches quietly altered answers. Teams shipping RAG and agent features pay.

Competitive · Benchmark exposes near-target prompt injection

Written for: Solo builder

Next step

Write 50 near-target injections against a sample invoice-summary RAG app, score field diffs against clean answers, and release them as a promptfoo plugin. Post the failure rates for three models as a Show HN and in the promptfoo Discord.

Why now

Current guard tools and test suites measure whether an agent abandons the user's task. They don't measure whether a total, vendor name or deadline quietly changed. Any product that summarises emails, invoices or web pages is exposed, and nothing on the market tests this class directly. Our earlier cards (Fetch Guard, Hidden Ask, BEC Range) filtered or simulated attacks. This one is a regression test for a failure mode that wasn't named until now.

What became possible

A new benchmark defines near-target prompt injection. These attacks don't try to hijack the agent. They make small changes that keep most of a legitimate answer and make it wrong or harmful. A system can score well on today's injection benchmarks just by refusing obvious hijacks, and still accept these edits.

Three ways in

  1. near-miss generator

    Takes your own documents and plants near-target instructions (change a number, swap a recommended vendor, move a date). It runs your pipeline and diffs the output against a clean run.

    Customer
    Small teams building RAG, inbox or summarisation features
    Model
    Open-source core; $49/month for hosted suites and history
  2. promptfoo plugin

    Packages the attack set as a promptfoo-compatible provider so teams add it to evals they already run.

    Customer
    Developers already using promptfoo
    Model
    Free plugin that feeds the hosted product
  3. Finance doc pack

    Curated near-target attacks on invoices, bank statements and contracts, scored on field-level changes.

    Customer
    Indie fintech and bookkeeping-automation builders
    Model
    $199 one-off pack plus updates

Competition

Competitive

Indirect prompt injection testing is already a busy space. Promptfoo and garak ship open-source plugins and probes, AgentDojo and OpenRAG-Soc are academic benchmarks, and Repello sells an enterprise platform.

Full competition notes (9 competitors)

Indirect prompt injection testing is already a busy space. Promptfoo and garak ship open-source plugins and probes, AgentDojo and OpenRAG-Soc are academic benchmarks, and Repello sells an enterprise platform. That leaves the plain promptfoo-plugin idea in a weak spot: promptfoo already has an indirect-prompt-injection plugin that runs against RAG context, and it could add a near-miss payload style cheaply. What I found is generally framed around catching the model obeying an attacker: going off-task, leaking data, running a payload. AgentDojo's banking tasks, like changing a payment recipient, are the closest prior art, but they live in a fixed benchmark. I did not see a product that takes a team's own documents, plants a believable change that serves the task (a different number, vendor or date), runs the real pipeline, and reports field-level differences from a clean baseline run. That integrity angle is where a new entrant could still win. The finance pack is the strongest wedge, because invoice and bank-detail fraud through hidden text is a well-understood threat that buyers already worry about, and field-level scoring of invoices and statements is concrete and easy to sell to bookkeeping-automation builders. The risks are that promptfoo or garak copy the payload style, and that small teams may not pay for a test pack. Shipping it as a CI-friendly diff harness with a curated, regularly refreshed domain attack corpus, with the promptfoo integration as a way in rather than the product, is the most defensible route.

  • Promptfoo indirect-prompt-injection and RAG red-team plugins

    The most direct overlap, especially with your plugin idea. It puts payloads into a named untrusted variable (RAG context, document, email) and fails the test if the model follows them. Its RAG guide adds document-exfiltration testing. The examples I found judge whether the model obeyed the payload. I saw nothing that diffs field-level output against a clean run on the user's own corpus.

  • NVIDIA garak latentinjection probes

    An open-source scanner with probes that hide injections inside context, including fact-snippet probes whose stated goal is to subvert a snippet with instructions. It is model-level and template-driven. It does not plant attacks in a team's own documents or diff outputs.

  • AgentDojo

    An academic benchmark whose banking suite includes near-miss-style injection tasks, such as changing the recipient of a recurring payment or sending to an attacker's IBAN. It shows the attack class is known. It is a fixed environment, though, not a tool you run against your own pipeline.

  • OpenRAG-Soc (Hidden-in-Plain-Text benchmark)

    A 2026 benchmark and harness for indirect injection and retrieval poisoning in web-facing RAG. It measures attack success at answer time. It is a research artefact, not a product.

  • Rag 'n Roll

    A research framework for testing indirect manipulation end to end across RAG setups. It finds that most existing attacks are tuned to push malicious documents up the retrieval ranking.

  • Repello AI ARTEMIS

    A commercial red-teaming platform. By its own account it covers document injection, retrieval manipulation and indirect injection through retrieved content in RAG deployments. Aimed at enterprises.

  • IPI-proxy

    An open-source intercepting proxy from May 2026. It rewrites web responses to plant 820 known injection strings when red-teaming browsing agents. It covers the web rather than a team's own documents, and it uses generic payloads.

  • Gray Swan Arena IPI competition

    A crowdsourced indirect-injection red-teaming competition relaunched in October 2026 with backing from frontier labs. It signals strong interest and produces attack data, but it is not a test pack you run in your own CI.

  • VexRAG

    A research framework on PyPI that plants poisoned passages directly into a RAG retrieval index.

Checked 2026-10-26

Risks

  • Lakera, promptfoo or Protect AI (now part of Palo Alto Networks) could add the category within a month
  • Scoring 'subtly wrong' needs ground truth for each test document
  • Teams that have never been attacked may not prioritise it

Strong team fit; market pull is the weak point (5).

tech 8 · pull 5 · space 6 · fit 9 · build 8

Exposed

Companies that could benefit or be threatened. News and context, not investment advice.

Momentum of its main topic

163 developments this week +2 vs last week
27 Sep: 0 developments28 Sep: 0 developments29 Sep: 0 developments30 Sep: 0 developments1 Oct: 0 developments2 Oct: 0 developments3 Oct: 0 developments4 Oct: 0 developments5 Oct: 0 developments6 Oct: 0 developments7 Oct: 0 developments8 Oct: 32 developments9 Oct: 26 developments10 Oct: 13 developments11 Oct: 11 developments12 Oct: 14 developments13 Oct: 19 developments14 Oct: 24 developments15 Oct: 35 developments16 Oct: 31 developments17 Oct: 15 developments18 Oct: 14 developments19 Oct: 23 developments20 Oct: 26 developments21 Oct: 36 developments22 Oct: 30 developments23 Oct: 30 developments24 Oct: 15 developments25 Oct: 7 developments26 Oct: 19 developments
Stage: Coverage

Sources

  1. On Task, Off Track: Benchmarking LLM and Agent Robustness to Near-Target Prompt InjectionarXiv

Status history

  • 2026-10-26 Flagged as buildable