# CVE-2026-126932: Zipline 4.6.2 before 4.8.0 Disabled MIME Type Policy Bypass via File Metadata Update

Status: published. Published: 2026-11-11. Updated: 2026-11-11.

Zipline 4.6.2 before 4.8.0 contains a policy bypass vulnerability that allows authenticated users to evade administrator-disabled MIME types by editing file metadata. Attackers can upload a permitted file, then set a disabled type such as text/html through PATCH /api/user/files/:id so /raw/:id serves that Content-Type.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/diced/zipline/commit/fc8e886ca841b86a3f677cd7dac1bf9a5bd45b2c

## Affected products and versions

- diced / zipline (diced/zipline): ≥ 4.6.2; < 4.8.0 (affected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 5.3 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 4.3 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N; source: CNA: VulnCheck

- CVSS 4.0: 5.3 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/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; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 4.3 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-434

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/diced/zipline/security/advisories/GHSA-rgxm-54cf-whf7 (CNA: VulnCheck; vendor-advisory)

- https://github.com/diced/zipline/commit/fc8e886ca841b86a3f677cd7dac1bf9a5bd45b2c (CNA: VulnCheck; patch)

- https://github.com/diced/zipline/releases/tag/v4.8.0 (CNA: VulnCheck; release-notes)

- https://github.com/diced/zipline/blob/v4.7.0/src/server/routes/api/user/files/%5Bid%5D/index.ts#L96 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/zipline-4.6.2-before-4.8.0-disabled-mime-type-policy-bypass-via-file-metadata-update (CNA: VulnCheck; third-party-advisory)

- https://github.com/diced/zipline/blob/v4.7.0/src/server/routes/api/user/files/%5Bid%5D/index.ts#L96 (disclosure@vulncheck.com)

- https://github.com/diced/zipline/commit/fc8e886ca841b86a3f677cd7dac1bf9a5bd45b2c (disclosure@vulncheck.com)

- https://github.com/diced/zipline/releases/tag/v4.8.0 (disclosure@vulncheck.com)

- https://github.com/diced/zipline/security/advisories/GHSA-rgxm-54cf-whf7 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/zipline-4.6.2-before-4.8.0-disabled-mime-type-policy-bypass-via-file-metadata-update (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-126932; retrieved 2026-11-11; source updated 2026-11-11

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-126932; retrieved 2026-11-12; source updated 2026-11-11

Revision: 46a551119a9c7e430e3639910f0ba6884fbaf4a7f2e6a3204819afa60fa42d3d

Canonical: https://y2.dev/cve/CVE-2026-126932

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.