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TI-2026-24639 Aliases CVE-2026-32101GHSA-mm78-fgq8-6pgr

StudioCMS S3 Storage Manager Authorization Bypass via Missing `await` on Async Auth Check

Priority HIGH 66CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · High · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-863.

Summary

StudioCMS is a server-side-rendered, Astro native, headless content management system. Prior to 0.3.1, the S3 storage manager's isAuthorized() function is declared async (returns Promise<boolean>) but is called without await in both the POST and PUT handlers. Since a Promise object is always truthy in JavaScript, !isAuthorized(type) always evaluates to false, completely bypassing the authorization check. Any authenticated user with the lowest visitor role can upload, delete, rename, and list all files in the S3 bucket. This vulnerability is fixed in 0.3.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00213 11th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed s3-storage (@studiocms): 0.3.1@studiocms/s3-storage (npm): 0.3.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
withstudiocmss3-storagebefore 0.3.10.3.1Patch availableCNA
—@studiocms/s3-storage (npm)before 0.3.10.3.1Patch availableGHSA-mm78-fgq8-6pgr
  • s3-storage Vendorwithstudiocms Affected before 0.3.1 Fixed in 0.3.1 Patch available CNA
  • @studiocms/s3-storage (npm) Vendor— Affected before 0.3.1 Fixed in 0.3.1 Patch available GHSA-mm78-fgq8-6pgr

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:studiocms:studiocms:*:*:*:*:*:*:*:*before 0.3.1Vulnerablewithstudiocms
  • cpe:2.3:a:studiocms:studiocms:*:*:*:*:*:*:*:* Versions before 0.3.1 Vulnerable ·withstudiocms

Remediation

  • Fix · CNA s3-storage (@studiocms) Fixed in 0.3.1
  • Fix · GHSA-mm78-fgq8-6pgr @studiocms/s3-storage (npm) Fixed in 0.3.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-32101
  2. 2026-10-03 Alias added: GHSA-mm78-fgq8-6pgr

References

Exploit 1

Advisory 1

Other 1

  • TI-2026-23769 StudioCMS Affected by Privilege Escalation via Insecure API Token Generation CVSS 3.1HIGH 8.8
  • TI-2026-24644 StudioCMS: REST API Missing Rank Check Allows Admin to Create Peer Admin Accounts CVSS 3.1HIGH 7.2
  • TI-2026-24641 StudioCMS: IDOR — Admin-to-Owner Account Takeover via Password Reset Link Generation CVSS 3.1HIGH 7.2
  • TI-2026-19452 StudioCMS has an Authorization Bypass Through User-Controlled Key CVSS 3.1MEDIUM 6.5
  • TI-2026-24642 StudioCMS: IDOR in User Notification Preferences Allows Any Authenticated User to Modify Any User's Settings CVSS 3.1MEDIUM 5.4
  • TI-2026-25147 StudioCMS REST getUsers Exposes Owner Account Records to Admin Tokens CVSS 3.1LOW 2.7
See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences