Auth bypass in Payloadcms Payload
CVE-2026-93363
The @payloadcms/storage-vercel-blob storage adapter for Payload contains an improper access control vulnerability that allows authenticated users to bypass collection-level permissions by accessing the client-upload route directly. Attackers can upload files through the client-upload endpoint without possessing the required collection access permissions, circumventing the intended access control enforcement.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (7.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 7.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-mc8m-rr6c-r5qr) (vendor-advisory)
- www.vulncheck.com/advisories/payload-cms-storage-vercel-blob-adapter-improper-a… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-93363?
- CVE-2026-93363 is a medium-severity vulnerability in Payloadcms Payload, classified under Missing Authorization. CVSS score: 4.3/10. Published 2026-09-25.
- How severe is CVE-2026-93363?
- Medium severity. CVSS v3 base score is 4.3 out of 10.