Vulnerability Report

CVE-2026-33221

Title: Arbitrary MIME type upload bypass in Nhost storage service

Other

Proof Of Concept

No public PoC currently indexed for CVE-2026-33221.

CWE Category CWE-343
Published Date Mar 20, 2026
Modified Date Jun 03, 2026
Exploit Status Not Found
Score 2.1 CVSS v4.0
Exploit Probability (EPSS)
0.01%

Vulnerability Summary

CVE-2026-33221: Nhost is an open source Firebase alternative with GraphQL. Prior to version 0.12.0, the storage service's file upload handler trusts the client-provided Content-Type header without performing server-side MIME type detection. This allows an attacker to upload files with an arbitrary MIME type, bypassing any MIME-type-based restrictions configured on storage buckets. This issue has been patched in version 0.12.0.

Impacted Vendors

S
storage_project 1
N
nhost 1

Reference Links

https://github.com/nhost/nhost/commit/c4bd53f042d7f568e567e18e2665af81660fce85 https://github.com/nhost/nhost/pull/4018 https://github.com/nhost/nhost/releases/tag/storage%400.12.0 https://github.com/nhost/nhost/security/advisories/GHSA-g9f6-9775-hffm
CVSS v4.0
Source Entity [email protected]
Severity LOW
2.1
Attack Vector
NETWORK
Complexity
HIGH
Privileges
N/A
Interaction
ACTIVE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
N/A
RAW VECTOR CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/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
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
5.3
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-33221 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity HIGH
Privileges N/A
Interaction ACTIVE
CVSS Vector String CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/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 Stack

No specific products linked.