CVE-2026-33221Nhost Storage Affected by MIME Type Spoofing via Trusted Client Content-Type Header in Storage Upload
- 2.1LowCVSS base score
- 0.19%Exploitation in 30 daysEPSS · top 91% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By GitHub_M
- 3 days later
· 3 days later
Published
- 5 days later
· 5 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | Low2.1 | 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 |
| NVDNVD · Analyzed | 4.0 | Low2.1 | 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 |
- EPSS (exploitation in 30 days)
- 0.19% · top 91% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.1.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/nhost/nhostGHSA-g9f6-9775-hffm (opens in a new tab)
References
References4
- https://github.com/nhost/nhost/security/advisories/GHSA-g9f6-9775-hffm (opens in a new tab)x_refsource_CONFIRM
- https://github.com/nhost/nhost/pull/4018 (opens in a new tab)x_refsource_MISC
- https://github.com/nhost/nhost/commit/c4bd53f042d7f568e567e18e2665af81660fce85 (opens in a new tab)x_refsource_MISC
- https://github.com/nhost/nhost/releases/tag/storage%400.12.0 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-13877 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-g9f6-9775-hffm (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-33221)Record last updated .