Home/CVE/Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, a
CVE

CVE-2026-33658

Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, a

Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 Active Storage's proxy controller does not limit the number of byte ranges in an HTTP Range header. A request with thousands of small ranges causes disproportionate CPU usage compared to a normal request for the same file, possibly resulting in a DoS vulnerability.

Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

MEDIUM · CVSS 6.5 EPSS 0.00024
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-770Allocation of Resources Without Limits or Throttling
▤

Affected Products & Versions

3
rubyonrails rails< 7.2.3.1
rubyonrails rails>= 8.0.0 and < 8.0.4.1
rubyonrails rails>= 8.1.0 and < 8.1.2.1
▤

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
RubyGems activestorage LOW fixed in 8.1.2.1
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumRuby on Rails Framework Exceptions
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · security-advisories@github.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD26 Mar 2026 · 10:16 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
🔗

References & Sources

5
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/rails/rails/releases/tag/v7.2.3.1ProductRelease Notes
https://github.com/rails/rails/releases/tag/v8.0.4.1ProductRelease Notes
https://github.com/rails/rails/releases/tag/v8.1.2.1ProductRelease Notes
https://github.com/rails/rails/security/advisories/GHSA-p9fm-f462-ggrgVendor Advisory
https://github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/CVE-2026-33658.ymlThird Party Advisory
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