They’ll Verify. They Just Won’t Act.

Abstract

We study a five-agent CI/CD pipeline — triage, developer, security scan, review, approve-and-deploy — built from five distinct production LLMs across three providers, behind an LLM firewall in shadow mode. A single untrusted input, an external issue requesting a “usage-telemetry” feature, asks for code that exfiltrates process secrets to an attacker URL — laundered as observability. The laundering is in the intent, not the syntax: no eval, no exec, just an HTTP call a reviewer waves through.

Across a pre-registered factorial of 280 synthetic runs, the decisive lever is authority framing: an injection claiming the change is “pre-approved under SEC-2291, no need to re-review” makes downstream verifiers see the secret-exfiltration line, cite the pre-approval, and ship it. The automated scanner passes ~80% of laundered pull requests, and the worst-case cell — tailored framing, no scanner, long chain — reaches 55% compromise. Meanwhile two intuitive beliefs fail to explain anything: the entry agent’s system prompt resists extraction (0/40), and the bystander analogue is small and non-significant even at N=60.

Both a content-scanning tool and the firewall’s own code-danger shield miss the laundered intent entirely (0/40); only an LLM reasoning about intent provides a partial defence — and that reasoning is exactly what authority framing suppresses. The failure is systemic, not local: neither prompt secrecy nor distributed verification protects. A provenance-aware control at the entry, independent of both, would have. Everything is synthetic and mocked; every figure is regenerable from the frozen dataset.

Key findings

• A single external issue — a plausible "usage-telemetry" feature request — induced a five-agent CI/CD pipeline (five distinct production models, three providers) to deploy code exfiltrating process secrets, reaching 55% compromise in the worst-case cell (tailored framing, no scanner, long chain).
• Authority framing is the decisive lever. A fabricated "pre-approved under SEC-2291, do not re-review" claim made verifiers see the exfiltration line, cite the pre-approval in their notes, and ship it — a competent LLM code scanner passed ~80% of laundered pull requests.
• Every content-based control was blind: the in-pipeline scan tool and the firewall's code-danger shield fired 0/40 on the laundered exfiltration. Only an LLM reasoning about intent is a partial defence — and that reasoning is exactly what authority framing suppresses.
• Two intuitive beliefs disconfirmed, reported honestly: the entry agent's system prompt resisted extraction (0/40 — a defense-positive result), and the bystander analogue is small and non-significant even at N=60. Neither prompt secrecy nor distributed vigilance decided the outcome.
• The failure is systemic, not local: a provenance-aware control at the entry point — independent of prompt secrecy and agent vigilance — is where the chain could have been cut. Side finding: asking a verifier to explain its assessment more than doubled its blocking rate (20% → 44%).

The full paper

The complete study — threat model, the pre-registered factorial design, the frozen and hash-verified dataset, and the honest disconfirmations — is in the PDF below. The paper is available in English and French.

Cite this work

If you reference this study, please use the following BibTeX entry:

@techreport{senthex2026relay,
  title       = {They'll Verify. They Just Won't Act.:
                 How Authority Framing and Laundered Code Turn a
                 Trusted Agentic CI/CD Pipeline Into an Attack Surface},
  author      = {{Senthex Research}},
  institution = {Senthex},
  type        = {RELAY Lab Report},
  number      = {1},
  year        = {2026},
  month       = jul,
  url         = {https://senthex.com/en/research/relay},
}