CVE-2026-91987 json
atomic-agents-stack before 1.1.0 Cost Guardrail Bypass via Unknown Model
published 2026-08-17 2 mo ago modified 2026-09-24 45 d ago also GHSA-j659-8xh6-5pq5 , EUVD-2026-78658
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 41%
- public exploits
- 0
- none known
Summary
atomic-agents-stack before 1.1.0 contains a cost-guardrail bypass in the _estimate_batch_cost function that returns zero cost for unknown models not in the pricing table. Attackers can configure deployments with unknown model identifiers to bypass daily cost caps and exceed budget limits in parallel batch operations.
Patch / fix
- pypi atomic-agents-stack 1.1.0
- dep0we atomic-agents-stack 1.1.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 52 d ago
Exploit prediction
0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | atomic-agents-stack | <1.1.0 |
1.1.0 |
Affected products
- dep0we atomic-agents-stack
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/dep0we/atomic-agents-stack/security/advisories/GHSA-j659-8xh6-5pq5
vendor-advisory, web
-
vulncheck.com
/advisories/atomic-agents-stack-before-1.1.0-cost-guardrail-bypass-via-unknown-model
third-party-advisory
-
github.com
/dep0we/atomic-agents-stack
package
-
github.com
/dep0we/atomic-agents-stack/releases#release-v1.1.0
web
Sources
- CVE List CVE-2026-91987
- GitHub Advisory GHSA-j659-8xh6-5pq5
- NVD CVE-2026-91987
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