CVE-2026-75627 (GCVE-0-2026-75627)
Vulnerability from cvelistv5 – Published: 2026-08-18 10:46 – Updated: 2026-08-18 11:18
VLAI
EPSS
VEX
Title
Bastillion Authentication Bypass via Path-Prefix Routing Mismatch
Summary
Bastillion fails to properly validate request URI paths in its controller dispatcher, allowing unauthenticated attackers to bypass authentication filters by prefixing requests with arbitrary path segments. Attackers can access administrative controllers to read user listings, create manager accounts, and register managed systems, gaining control over SSH access to the managed fleet.
Severity
9.8 (Critical)
CWE
- CWE-288 - Authentication Bypass Using an Alternate Path or Channel
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/bastillion-io/Bastillion/issues/669 | issue-tracking |
| https://github.com/bastillion-io/Bastillion | product |
| https://github.com/bastillion-io/Bastillion/commi… | patch |
| https://github.com/bastillion-io/Bastillion/blob/… | technical-description |
| https://www.vulncheck.com/advisories/bastillion-a… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| bastillion-io | Bastillion |
Affected:
0 , ≤ 5.1.0
(custom)
|
guessed |
Date Public
2026-08-17 00:00
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},
{
"tags": [
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],
"url": "https://github.com/bastillion-io/Bastillion"
},
{
"name": "Fix unauthenticated admin bypass, harden WS terminal auth, add login throttling",
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"url": "https://github.com/bastillion-io/Bastillion/commit/d759fb686a1a097b1b026e286fd9b20e5ba349c8"
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},
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}
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"title": "Bastillion Authentication Bypass via Path-Prefix Routing Mismatch",
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"datePublished": "2026-08-18T10:46:54.674Z",
"dateReserved": "2026-08-18T01:03:25.541Z",
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"state": "PUBLISHED"
},
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"vulnerability-lookup:meta": {
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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