CVE-2026-18636 (GCVE-0-2026-18636)

Vulnerability from cvelistv5 – Published: 2026-08-11 14:40 – Updated: 2026-08-11 19:43
VLAI
Title
Velociraptor VFSGetBuffer API path deny list bypass
Summary
The Velociraptor gRPC API has a VFSGetBuffer endpoint which allows reading files from the datastore. To prevent users from reading sensitive files or accessing other orgs, the requested path is prefix checked against a list of denied prefixes. This prefix check can be bypassed allowing a user to access usually denied files. If the user has read permission in the ROOT org, this allows access to other orgs, in which the user may not have permission.
Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-11 19:25 UTC
CWE
  • CWE-288 - Authentication bypass using an alternate path or channel
Assigner
References
Impacted products
Vendor Product Version CPE status
Rapid7 Velociraptor Affected: 0 , < 0.77.2 (semver)
guessed Create a notification for this product.
Credits
Itay Vardi
Show details on NVD website
To clipboard 

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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

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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.
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  • 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.
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