CVE-2026-18636 json
Velociraptor VFSGetBuffer API path deny list bypass
published 2mo ago modified 17d ago also EUVD-2026-56178
- cvss
- 6.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 34%
- public exploits
- 0
- none known
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.
Patch / fix
- Rapid7 Velociraptor 0.77.2
- velociraptor openSUSE Tumbleweed 0.76.7.0.git145.b60ef1146-1.1
opensuse advisories openSUSE-SU-2026:12070-1
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N |
Affected products
- Rapid7 Velociraptor
Classification
- Weakness
-
- CWE-288 Authentication Bypass Using an Alternate Path or Channel
References
Sources
- CVE List CVE-2026-18636
- NVD CVE-2026-18636
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