CVE-2026-126085
Published:November 10, 2026
Updated:November 14, 2026
Active Storage makes it simple to upload and reference files in cloud services and attach those files to Active Record objects. Prior to 8.1.4.1 and 8.0.5.2, ActiveStorage::Service::GCSService#url_for_direct_upload does not bind the declared content length into the signed direct-upload URL, and #headers_for_direct_upload returns no length constraint, so the URL authorizes an upload body of any size. A direct-upload client could store a file larger than the byte_size it declared, and the resulting blob keeps the declared size, possibly bypassing application file size validations and quotas. This is the weakness that CVE-2020-8162 fixed in the S3 service. Applications that store files in Google Cloud Storage and accept direct uploads are affected. This issue is fixed in versions 8.1.4.1 and 8.0.5.2.
Affected Packages
https://github.com/rails/rails.git (GITHUB):
Affected version(s) >=v8.1.0.beta1 <v8.1.4.1Fix Suggestion:
Update to version v8.1.4.1https://github.com/rails/rails.git (GITHUB):
Affected version(s) >=v5.2.0.beta1 <v8.0.5.2 || >=v6.0.0.beta1 <v8.0.5.2 || >=v7.0.0.alpha1 <v8.0.5.2 || >=v8.0.0.alpha1 <v8.0.5.2Fix Suggestion:
Update to version v8.0.5.2activestorage (RUBY):
Affected version(s) >=5.2.0.beta1 <8.0.5.2 || >=8.0.0.beta1 <8.0.5.2 || >=6.0.0.beta1 <8.0.5.2 || >=7.0.0.alpha1 <8.0.5.2Fix Suggestion:
Update to version 8.0.5.2activestorage (RUBY):
Affected version(s) >=8.1.0.beta1 <8.1.4.1Fix Suggestion:
Update to version 8.1.4.1Related Resources (9)
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Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Client-Side Enforcement of Server-Side Security
EPSS
Base Score:
0.48