Bastillion Authentication Bypass via Path-Prefix Routing Mismatch
Priority HIGH 81CWE-288Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-288.
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.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00844 58th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| bastillion-io | Bastillion | up to 5.1.0 | — | No fix listed | CNA |
- Bastillion Vendorbastillion-io Affected up to 5.1.0 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-75627
- 2026-10-03 Alias added: GHSA-9v44-g22g-qfg5
References
More bastillion-io vulnerabilities
- TI-2026-00797 bastillion-io Bastillion System Management SystemKtrl.java command injection CVSS 4.0MEDIUM 5.1
- TI-2026-00796 bastillion-io Bastillion Public Key Management System AuthKeysKtrl.java command injection CVSS 4.0MEDIUM 5.1
Sources
- CVE-2026-75627 · CVE Program
- CVE-2026-75627 · NVD
- FIRST EPSS
- GHSA-9v44-g22g-qfg5 · GitHub Advisory Database · CC BY 4.0
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