Trojan-Based Data Poisoning Attacks Increasing LLM Token Response Costs

# Trojan-Based Data Poisoning Attacks Increasing LLM Token Response Costs

https://gcdradar.vercel.app/incidents/trojan-based-data-poisoning-attacks-increasing-llm-token-res · AIR-2026-1418 · closed 2026-11-03

- Lane: Research
- Severity: 1 (Research / proof of concept)
- Fix status: Fix status unknown
- First reported: 2026-10-20
- AI role: Attack on AI

## Summary

Researchers devised a defense against a data-poisoning attack that plants a Trojan to artificially increase LLM response lengths and financial costs. The attack triggers on semantically similar instructions within prompts.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-10-20: LLM Trojans that Increase Response Lengths and Cost (https://arxiv.org/abs/2610.24784)

## Sources

- 2026-10-20 arXiv: LLM Trojans that Increase Response Lengths and Cost https://arxiv.org/abs/2610.24784

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.