STUPID-2026-0056

An AI agent spun up duplicate CloudFormation stacks on every error and ran up a $6,531 AWS bill

5.0medium
June 12, 2026Source checked

Why 5/10

$6,531 of AWS charges from a retry loop. Whether any was refunded is not stated.

Scope
1/4
A few files, one session, one credential, or a small cost
Recoverability
2/3
Partly lost, or loss reported without saying whether it was recovered
Did it happen
2/2
Happened in real use
Beyond the user
0/1
Only the user's own non-production work

The score is the sum of these four factors. How each factor is scored · scored 2026-10-29

  1. Instruction given

    Register for the DN42 hobbyist network.

  2. Expected behavior

    Stop and ask for help after repeated failures instead of retrying destructively.

  3. Actual behavior

    The agent kept spinning up duplicate AWS CloudFormation stacks every time it hit an error, because nobody told it to stop, running up a $6,531.30 AWS bill on what should have been a hobbyist-network registration task.

  4. Damage

    $6,531.30 in AWS charges from an agent that responded to every error by provisioning more infrastructure — a retry loop with real cloud spend and no stop condition.

Full write-up

On June 12, 2026, an AI agent tasked with something as minor as registering for the DN42 hobbyist network ran up a $6,531.30 AWS bill. Its failure strategy was the problem: every time it hit an error, it spun up a duplicate CloudFormation stack and tried again, because nobody had told it to stop. With no cost guard or halt condition, an error-handling loop turned into an infrastructure-provisioning loop that billed real money on each iteration. It is a compact illustration of why agentic tools with cloud access need hard spend caps: the agent never 'crashed' — it kept confidently doing more of exactly the wrong thing.

Classification

Agent
Unknown agent
Failure mode
Infinite Loop
Root cause
Confidence Miscalibration
Domain
Infra
OWASP Agentic Top 10 (our mapping)
ASI02 Tool Misuse and Exploitation list
MIT AI Risk Repository (our mapping)
7.3 Lack of capability or robustness taxonomy
Source
News Report

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Cite this record
StupidLLM. "STUPID-2026-0056: An AI agent spun up duplicate CloudFormation stacks on every error and ran up a $6,531 AWS bill." AI Agent Incident Database, 2026. https://www.stupidllm.com/incident/STUPID-2026-0056/ (accessed 2026-10-29). CC BY 4.0.

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