AnalysisPublished 23 Sep 2026

Cybersecurity Tokenomics: Denial of Wallet Attacks | Kaspersky official blog

Source Kaspersky Security Blog

Description

This analysis discusses a new type of denial-of-service attack against AI agents called "denial of wallet," where attackers exploit the pay-as-you-go token consumption model of large language models (LLMs) to cause excessive financial costs. Autonomous AI agents that operate continuously and retry failed steps can consume tokens unpredictably and in large bursts, making costs difficult to control. Attackers can exploit this by sending numerous complex or looping requests that inflate token usage, leading to significant budget overruns. This issue has been recognized as a top risk in the OWASP guide for language models (LLM06:2026).

Impact

The primary impact is financial, with organizations potentially incurring massive unexpected costs due to manipulated AI agent workflows that consume excessive tokens. This can disrupt operational budgets and cause financial strain. Additionally, the unpredictability of token consumption complicates cost management and budgeting. While no direct compromise of data or systems is described, the attack affects operational stability and reliability by exhausting AI resources and budgets. The attack can be repeated at no cost to the attacker, amplifying potential damage.

Defensive guidance

Organizations should avoid deploying autonomous AI agents for all tasks indiscriminately and implement strict cost monitoring and limits on AI usage. Employing specialized cost accounting and management systems (akin to FinOps in cloud services) can help detect and control anomalous token consumption. Periodic reviews of AI agent tasks and restricting external inputs that could trigger excessive retries or loops are recommended. Vendors and organizations should collaborate to develop better token consumption controls and anomaly detection mechanisms.

Summary

The threat involves malicious actors targeting AI agents that use large language models with pay-as-you-go billing by deliberately causing excessive token consumption, effectively a "denial of wallet" attack. Because LLMs are stateless and require the entire context to be resent with each step, iterative or failing tasks increase token usage exponentially. Autonomous agents that operate without human intervention can incur unpredictable and very high costs, especially if attackers trigger repeated retries or thought loops. This can lead to financial damage, as demonstrated by cases where companies overspent millions due to uncontrolled token usage. The OWASP Top Risks for Language Models now explicitly identifies unbounded token consumption and denial of wallet attacks as critical concerns.

References

kaspersky.com/blog/tokenomics-ai-cost-ddos/56455/ (opens in a new tab)

Community reviews

Loading reviews…

Description

AI analysisMachine-generated, updated 23 Sep 2026, 14:46 UTC

References

Community reviews

Related threats