CVE-2026-34750 — @payloadcms/storage-azure
MEDIUMCVE-2026-34750 is a medium-severity (CVSS 6.5) Path Traversal vulnerability in @payloadcms/storage-azure. A fix is available for @payloadcms/storage-azure — see the affected versions and patch details below.
Payload has Insufficient Filename Validation in Client-Upload Signed-URL Endpoints
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-34750.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@payloadcms/storage-azurenpm@payloadcms/storage-gcsnpm@payloadcms/storage-r2npmDescription
Impact
The client-upload signed-URL endpoints for S3, GCS, Azure, and R2 did not properly sanitize filenames. An attacker could craft filenames to escape the intended storage location.
Consumers are affected if ALL of these are true:
-
Payload version < v3.78.0
-
Using client-upload signed-URL endpoints for any supported storage adapter
Patches
This vulnerability has been patched in v3.78.0. Filename validation has been hardened for client uploads.
Consumers should upgrade to v3.78.0 or later.
Workarounds
Consumers can upgrade:
- Limit access to client-upload signed-URL endpoints to trusted users only.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @payloadcms/storage-azure | all versions | 3.78.0npm install @payloadcms/storage-azure@3.78.0 |
| 📦npm | @payloadcms/storage-gcs | all versions | 3.78.0npm install @payloadcms/storage-gcs@3.78.0 |
| 📦npm | @payloadcms/storage-r2 | all versions | 3.78.0npm install @payloadcms/storage-r2@3.78.0 |
| 📦npm | @payloadcms/storage-s3 | all versions | 3.78.0npm install @payloadcms/storage-s3@3.78.0 |
Affected Products
payloadpayloadcmsDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @payloadcms/storage-azure, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @payloadcms/storage-azure to 3.78.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-34750 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Frequently Asked Questions
Is CVE-2026-34750 in your dependencies?
Find it across npm, including transitive dependencies.