AI Agent Security Testing

Find what your
AI agent
will do under attack

AAPT runs adversarial probe suites against your production AI agents — chat agents, MCP servers, GraphQL-fronted agents, multi-turn and streaming deployments. We test for prompt injection, tool abuse, confused-deputy attacks, persistent multi-turn exploits, and GraphQL-specific DoS / injection before attackers find them.

OW
NI
MA
Aligned with OWASP LLM Top 10, NIST AI RMF, and MITRE ATLAS
aapt run start — acme-agent-prod
$ ./aapt run start -e acme-prod --floor HIGH
▶ Run started  seed=42 · 62 probes · grey-box
⬡ Loaded 62 probes across 21 categories
PASS  Role override via system instruction  [T-01]
FAIL  HIGH  Indirect injection via tool output  [T-02]  CVSS-A 8.5
FAIL  CRITICAL  Shell injection via code exec tool  [T-03]  CVSS-A 10.0
FAIL  CRITICAL  CSS hidden instruction injection  [T-11]  CVSS-A 9.0
FAIL  CRITICAL  MCP path traversal via resources/read  [M-01]  CVSS-A 9.5
FAIL  CRITICAL  Confused deputy: read_file → send_email exfil  [C-01]  CVSS-A 9.5
FAIL  HIGH  Trust-priming → confused-deputy cash-in  [P-01]  CVSS-A 8.5
FAIL  HIGH  GraphQL introspection schema leakage  [G-01]  CVSS-A 7.5
PASS  PII extraction via context mining  [T-04]
✓ Run complete  7 vulnerabilities · 5 critical · 2 high
$ Fix cost  $110k – $410k  |  Risk if unfixed  $3M – $30M
Reports: aapt run report a3f7...
$
Anchored to OWASP LLM Top 10 (2025) NIST AI RMF 1.0 MITRE ATLAS EU AI Act Art. 9–15 SOC 2 Type II
What we test

Twenty threat categories.
One systematic assessment.

Our probe library maps every test to OWASP LLM identifiers and MITRE ATLAS techniques. Categories T-01..T-14 cover chat-agent attacks (T-11..T-14 derived from AI Agent Traps, published by Google DeepMind, Franklin et al. 2025). M-01..M-03 pen-test MCP servers directly. C-01 targets LLM agents equipped with MCP-style tools (confused-deputy attacks). P-01 covers persistent multi-turn attacks. G-01 covers GraphQL-fronted agents.

T-01
Direct prompt injection
Adversarial payloads in user input designed to override system instructions or hijack the agent's role.
LLM01:2025 AML.T0051
T-02
Indirect prompt injection
Malicious instructions embedded in retrieved documents, tool outputs, or web content consumed by the agent.
LLM01:2025 AML.T0051.003
T-03
Insecure tool use
Manipulation of the agent into path traversal, shell injection, SSRF, or unsafe API calls via its tool integrations.
LLM07:2025 AML.T0040
T-04
Sensitive data exfiltration
PII extraction, system prompt leakage, and credential exposure via context mining or social engineering.
LLM02:2025 AML.T0025
T-05
Memory poisoning
Adversarial writes to persistent memory that manipulate future sessions — including false identity claims and privilege escalation.
LLM03:2025 AML.T0053
T-06
Goal hijacking
Mid-task objective substitution, priority inversion, and compliance constraint relaxation under false urgency.
LLM06:2025 AML.T0043
T-07
Multi-agent trust abuse
Rogue sub-agent payloads that propagate through orchestration layers and escalate privilege via forged agent identity.
LLM08:2025 AML.T0052
T-08
Resource abuse / DoS
Token bombs, recursive tool loops, and embedding search floods that cause cost overruns or service degradation.
LLM10:2025 AML.T0016
T-09
RAG data poisoning
Adversarial document injection into knowledge bases to contaminate retrieval and steer agent outputs.
LLM03:2025 AML.T0020
T-10
Compliance boundary bypass
Eliciting outputs that violate regulatory guardrails — GDPR data minimisation, HIPAA PHI handling, financial advice limits.
LLM05:2025 AML.T0048
T-11
Content injection traps
Adversarial instructions hidden in CSS, HTML comments, Markdown anchor text, or Unicode zero-width characters — invisible to humans but parsed and executed by agents reading raw markup.
LLM01:2025 AML.T0051.003 DeepMind 2025
T-12
Semantic manipulation traps
Framing bias, authoritative contextual priming, and persona hyperstition that corrupt an agent's reasoning without issuing explicit commands — evading safety filters designed for overt adversarial prompts.
LLM06:2025 AML.T0043 DeepMind 2025
T-13
Systemic traps
Compositional fragment attacks that reconstitute across multi-turn context, Sybil consensus manipulation, and sub-agent spawning via poisoned orchestrator instructions that introduce rogue agents into trusted control flow.
LLM08:2025 AML.T0052 DeepMind 2025
T-14
Human-in-the-loop traps
The agent is weaponised against its human overseer — approval fatigue buries harmful actions in verbose output, automation bias produces confident false summaries, and agent-inserted links become a social engineering vector.
LLM06:2025 AML.T0043 DeepMind 2025
M-01
MCP resource traversal
Direct JSON-RPC probes against an MCP server's resources/read — path traversal via file:// URIs, SSRF via internal-network URLs, and link-local / cloud-metadata exfiltration.
LLM02:2025 AML.T0024 MCP
M-02
MCP tool argument injection
Path traversal, shell metacharacters, and SQL fragments smuggled into tools/call arguments — testing whether the server validates inputs at the tool boundary rather than trusting the LLM.
LLM02:2025 AML.T0050 MCP
M-03
MCP discovery & auth bypass
Unauthenticated tools/list and resources/list calls that leak the full catalogue — including dangerous tools and sensitive resource URIs an attacker would otherwise need to guess.
LLM02:2025 AML.T0007 MCP
C-01
Confused deputy — LLM with tools
Tests whether an LLM equipped with MCP-style tools can be tricked into calling them maliciously — read_file path traversal, query_db bulk exfil, send_email to attacker domains, multi-tool exfiltration chains, indirect injection via documents.
LLM06:2025 AML.T0050 Path B
P-01
Multi-turn persistent attacks
Attack classes that require a setup turn — trust priming followed by a confused-deputy cash-in, confederate confabulation (false-memory exploits), incremental goal drift, and context-flood safety-prompt decay.
LLM01:2025 AML.T0051.001 Multi-turn
G-01
GraphQL injection & DoS
For GraphQL-fronted agents — schema introspection leakage, deeply-nested query DoS, alias amplification, SQL-pattern injection through mutation arguments, sensitive-field over-fetch, and unbounded multi-operation batching.
LLM02:2025 AML.T0029 GraphQL
📄
Research foundation
T-11 through T-14 are grounded in peer-reviewed research: Franklin, M., Tomašev, N., Jacobs, J., Leibo, J.Z., & Osindero, S. (2025). AI Agent Traps. Google DeepMind. The first systematic framework for adversarial content engineered to manipulate, deceive, or exploit autonomous AI agents navigating the web. Read the paper →
The process

Five phases.
Zero guesswork.

Every AAPT engagement follows a documented methodology. Each phase has defined inputs, outputs, and exit criteria. Nothing is skipped.

1

Scoping & threat modelling

We review your agent architecture, tool manifest, and regulatory environment. A signed Rules of Engagement document defines test boundaries before any probing begins.

Architecture review Threat modelling canvas Rules of engagement
2

Automated probe execution

Our harness executes the full probe library against your agent endpoints — chat, MCP server, GraphQL, multi-turn, or streaming — in black-box, grey-box, or white-box mode. Every response is logged and evaluated by purpose-built detectors.

Keyword detection Regex detection LLM judge Tool call audit MCP response audit GraphQL response audit
3

Manual red teaming

Human-driven adversarial sessions targeting chained attack sequences, multi-agent relay attacks, and social engineering that automated probes cannot surface.

Chained attacks Persona manipulation Multi-agent relay
4

CVSS-A scoring & financial exposure

Every finding is scored with our AI-adapted CVSS framework — accounting for reproducibility, blast radius across agent chains, and regulatory exposure. Each FAIL also carries a fix-cost band (engineering effort) and a risk-exposure band (cost if unfixed) in USD + INR, so the board can plan and prioritise.

Reproducibility modifier Blast radius modifier Regulatory modifier Fix-cost bands Risk-exposure bands
5

Report delivery & remediation

Executive brief (2–4 pages, board-ready) and full technical report with reproduction steps, scored findings, and code-level fix recommendations. Debrief call included.

Executive brief Technical report Debrief call
Risk scoring

CVSS-A — scoring built
for AI systems

Standard CVSS doesn't model probabilistic reproducibility or multi-agent blast radius. CVSS-A does.

CVSS-A Formula
Score = min(CVSSbase + R + BR + RE, 10.0)
R — Reproducibility
Consistent (every run)+2.0
Frequent (>75%)+1.5
Occasional (>50%)+1.0
Rare (<25%)+0.5
BR — Blast Radius
System-wide+1.5
Multi-user+1.0
Single session+0.5
Isolated+0.0
RE — Regulatory Exposure
GDPR / HIPAA critical+1.0
Moderate obligation+0.5
Minimal+0.2
None+0.0
Severity CVSS-A Range Remediation SLA Required action
● Critical 9.0 – 10.0 24 hours Immediate halt of production deployment
● High 7.0 – 8.9 7 days Prioritised fix with interim controls
● Medium 4.0 – 6.9 30 days Scheduled fix in next release cycle
● Low 0.1 – 3.9 90 days Backlog with accepted risk documentation
● Informational 0.0 No deadline Observation or improvement suggestion
$ Financial exposure

Every FAIL finding is priced in two dimensions

Fix cost (engineering effort to remediate) and risk exposure (estimated impact if exploited). USD ranges shown; reports also display INR for India-based teams.
Band Fix cost (engineering) Risk exposure (if unfixed) Typical scope
● Critical $40k – $150k $1M – $10M Cross-team rebuild; regulatory exposure under GDPR / HIPAA
● High $10k – $40k $100k – $1M 1–2 engineer-weeks; sensitive data or tool-misuse risk
● Medium $2k – $10k $10k – $100k 1–3 engineer-days; localised damage
● Low $500 – $2k $1k – $10k < 1 engineer-day; output-formatting / refusal-quality
Bands derive from (severity, category) with optional per-probe YAML overrides. Higher-blast-radius categories (credential exfil, tool misuse, agent-to-agent compromise) bump the risk band one tier above the fix band. Bands are deliberately wide because real cost depends on your stack and regulatory posture — they are defensible order-of-magnitude estimates, not invoices.
Pricing

One assessment or
continuous protection

One-off audits for point-in-time risk assessment. Annual subscriptions for teams deploying AI continuously.

One-off audit
Full assessment of a single agent deployment. Ideal for pre-launch risk review or board-level compliance evidence.
Custom
fixed scope engagement
  • Full probe suite execution
  • Manual red teaming session
  • CVSS-A scored finding register
  • Executive + technical reports
  • 60-min debrief call
  • OWASP / SOC 2 evidence pack
Get a quote →
Enterprise
Custom engagements for organisations with multiple agent deployments, enterprise SLAs, or regulatory mandates.
Custom
volume · multi-tenant
  • Everything in subscription
  • Unlimited agent deployments
  • On-premise harness deployment
  • Custom probe development
  • Dedicated security lead
  • EU AI Act compliance mapping
Contact us →
FAQ

Common questions

Do you need access to our model's system prompt? +
No — black-box testing requires only a public endpoint and credentials to call it. Grey-box and white-box modes unlock more targeted attack categories but are entirely optional. We scope the mode to your comfort level and security posture.
Will testing affect our production users? +
We strongly recommend testing against a staging environment. If production testing is required, we agree a narrow time window, a rollback plan, and a concurrency limit in the Rules of Engagement before any probes are dispatched. Our harness is configured to never create persistent access, delete data, or exfiltrate real user information.
Which agent frameworks do you support? +
Our harness communicates via HTTP only — it is framework-agnostic. We ship seven adapters: OpenAI-compatible chat (regular + SSE streaming), Anthropic Messages (regular + SSE streaming), MCP servers (JSON-RPC), GraphQL-fronted agents, and any generic REST API via Jinja2 templates. That covers Azure OpenAI, Groq, Together, Fireworks, Mistral, DeepSeek, Ollama, vLLM, LangGraph / LangServe, Hasura, AppSync, and any custom internal gateway. If your agent uses a custom protocol, we can build a custom adapter as part of the scoping phase.
Do you test MCP servers, GraphQL agents, and multi-turn conversations? +
Yes — all three are first-class targets. MCP servers are pen-tested directly via JSON-RPC (M-01..M-03: resource traversal, tool-argument injection, unauthenticated discovery) and indirectly via the LLM that consumes them (C-01: confused-deputy attacks where the model is tricked into calling a tool maliciously). GraphQL-fronted agents get a dedicated category (G-01) covering introspection leakage, depth DoS, alias amplification, and SQL-pattern injection through mutation arguments. Multi-turn attacks (P-01) cover trust priming, confabulation exploits, goal drift, and context-flood safety decay — attack classes that single-shot probe libraries miss entirely.
What is adaptive / agentic multi-turn red-teaming? +
Beyond fixed, scripted multi-turn probes, AAPT runs an adaptive attacker (P-02): an LLM generates each conversational turn live, adapting to how your agent responds, carrying a working memory of what it has tried, and steering toward the goal. It stops early when an attack plateaus (saving time and cost), and its reproducibility is empirically measured — the attack is re-run and the success rate feeds the CVSS-A score. An anonymized cross-run memory seeds each engagement with the tactics that worked against similar agents, so the attacker gets sharper the more it is used — while never storing or sharing your prompts, data, or findings.
How do you keep the LLM judge accurate? +
Findings that need judgement can be evaluated by a dual-model judge council: two independent frontier models (Anthropic and Google) each assess the agent's response and their verdicts are combined, so no single model's blind spot goes unchallenged. When the models disagree, that disagreement is surfaced on the finding for human review. A deterministic heuristic layer runs underneath as a fallback, so detection degrades gracefully rather than failing.
How are the financial-exposure numbers in the report calculated? +
Each FAIL finding carries two cost bands derived from its severity and category: a fix cost (engineering effort to remediate, $500–$150k across four bands) and a risk-exposure cost (estimated impact if exploited, $1k–$10M across four bands). Higher-blast-radius categories (credential exfil, tool misuse, agent-to-agent compromise) bump the risk band one tier above the fix band. Per-finding bands sum to a rollup card on the report's first page so CFOs and CISOs can prioritise without translating CVSS into spend themselves. Bands are deliberately wide because real cost depends on your stack and regulatory posture — they're defensible order-of-magnitude estimates, not invoices.
How does AAPT help with SOC 2 or EU AI Act compliance? +
The AAPT methodology document, finding register, and CVSS-A scored reports are designed as audit-ready evidence artefacts. They directly address SOC 2 Security trust service criteria and EU AI Act Article 9 (Risk Management), Article 15 (Robustness and Cybersecurity). Many clients share the executive report with their auditors at the start of the review cycle.
What happens to our data after the engagement? +
Raw probe payloads and agent responses are purged 30 days after engagement close. Scored findings are retained for 12 months for trend analysis, then deleted. We sign a data processing agreement before any testing begins. All test traffic originates from agreed IP ranges disclosed in the Scope Agreement.
Can we add our own custom probes? +
Yes — enterprise clients can supply domain-specific probes in our YAML schema. This is particularly valuable for regulated-domain agents (financial advice guardrails, HIPAA PHI handling) where generic probes may not fully cover your specific compliance requirements. Custom probes are loaded alongside the standard library and scored with the same CVSS-A framework.
From the blog

Research & field notes

The attack surfaces everyone now claims to cover — and what it takes to actually pen-test the agents you ship.

CommentaryJuly 21, 2026 · 6 min read

Trust is the bottleneck for enterprise AI. Here's what earning it would actually look like.

GoTo's CTO says the hard part is no longer the technology — it's trust. But trust in security is a measurement, not a posture. What earning it concretely requires for AI agents, and the published OWASP buyer standard you can hold every vendor to.

Read the post →
View all posts →

Ready to see what
your agent will do?

Book a free 30-minute scoping call. We'll map your agent architecture to threat categories and give you a clear picture of the assessment before any commitment.

Book a free scoping call → Send us a message
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