CVE-2026-91987Network attack vectorHinoki check available

Cost cap bypass via zero-cost model fallback

Published Sep 15, 2026 · Updated Sep 15, 2026

Cost guardrail bypass in dep0we atomic-agents-stack before 1.1.0 allows remote attackers to exceed daily caps through parallel batches. The _estimate_batch_cost function uses an empty pricing record for an unknown model, calculates a zero reservation, and makes _check_batch_reservation skip the only pre-batch cap reservation. Exploitation requires enabled cost guardrails and a daily cap, an unknown model identifier, and a parallel helper or delegate batch; the resulting spend can exceed the configured limit.

CVSS severity8.7
High
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
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Summary

What happened

Cost guardrail bypass in dep0we atomic-agents-stack before 1.1.0 allows remote attackers to exceed daily caps through parallel batches. The _estimate_batch_cost function uses an empty pricing record for an unknown model, calculates a zero reservation, and makes _check_batch_reservation skip the only pre-batch cap reservation. Exploitation requires enabled cost guardrails and a daily cap, an unknown model identifier, and a parallel helper or delegate batch; the resulting spend can exceed the configured limit.

The record

CVE
CVE-2026-91987
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
dep0we
Product
atomic-agents-stack
Classifications
CWE-770, T1496
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

dep0we · atomic-agents-stackversion=0 <1.1.0

Published CVSS scores

8.7GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1496Resource Hijacking

Public exploit references

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Technologies

Your stack

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Your stack

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