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TI-2026-25606 Aliases CVE-2026-33176GHSA-2j26-frm8-cmj9

Rails Active Support has a possible DoS vulnerability in its number helpers

Priority LOW 37CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 4 fixed, 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, Active Support number helpers accept strings containing scientific notation (e.g. `1e10000`), which `BigDecimal` expands into extremely large decimal representations. This can cause excessive memory allocation and CPU consumption when the expanded number is formatted, possibly resulting in a DoS vulnerability. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00858 58th percentileScored 2026-11-07
Fix Partial activesupport (rails): 8.1.2.1, 8.0.4.1, 7.2.3.1activesupport (RubyGems): 8.1.2.1, 8.0.4.1, 7.2.3.1Red Hat: 3 advisoriesRed Hat: 4 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
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
Railsactivesupport8.1.0.beta1 to before 8.1.2.1; 8.0.0.beta1 to before 8.0.4.1; before 7.2.3.18.1.2.1, 8.0.4.1, 7.2.3.1Patch availableCNA
—activesupport (RubyGems)8.1.0.beta1 to before 8.1.2.18.1.2.1Patch availableGHSA-2j26-frm8-cmj9
—activesupport (RubyGems)8.0.0.beta1 to before 8.0.4.18.0.4.1Patch availableGHSA-2j26-frm8-cmj9
—activesupport (RubyGems)before 7.2.3.17.2.3.1Patch availableGHSA-2j26-frm8-cmj9
  • activesupport VendorRails Affected 8.1.0.beta1 to before 8.1.2.1; 8.0.0.beta1 to before 8.0.4.1; before 7.2.3.1 Fixed in 8.1.2.1, 8.0.4.1, 7.2.3.1 Patch available CNA
  • activesupport (RubyGems) Vendor— Affected 8.1.0.beta1 to before 8.1.2.1 Fixed in 8.1.2.1 Patch available GHSA-2j26-frm8-cmj9
  • activesupport (RubyGems) Vendor— Affected 8.0.0.beta1 to before 8.0.4.1 Fixed in 8.0.4.1 Patch available GHSA-2j26-frm8-cmj9
  • activesupport (RubyGems) Vendor— Affected before 7.2.3.1 Fixed in 7.2.3.1 Patch available GHSA-2j26-frm8-cmj9

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*before 7.2.3.1; 8.0.0 to before 8.0.4.1; 8.1.0 to before 8.1.2.1VulnerableRails
  • cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:* Versions before 7.2.3.1; 8.0.0 to before 8.0.4.1; 8.1.0 to before 8.1.2.1 Vulnerable ·Rails

Remediation

  • Fix · CNA activesupport (rails) Fixed in 8.1.2.1, 8.0.4.1, 7.2.3.1
  • Fix · GHSA-2j26-frm8-cmj9 activesupport (RubyGems) Fixed in 8.1.2.1 Advisory →
  • Fix · GHSA-2j26-frm8-cmj9 activesupport (RubyGems) Fixed in 8.0.4.1 Advisory →
  • Fix · GHSA-2j26-frm8-cmj9 activesupport (RubyGems) Fixed in 7.2.3.1 Advisory →

Red Hat 3 advisories

  • RHSA-2026:14874 Released 2026-05-07 · Red Hat rating Important
    Satellite 6.16.8 Async Update
    • Red Hat Satellite 6.16 for RHEL 8 candlepin-4.4.25-1.el8sat, candlepin-selinux-4.4.25-1.el8sat, python-markdown-3.8.2-1.el8pc +6
    • Red Hat Satellite 6.16 for RHEL 9 candlepin-4.4.25-1.el9sat, candlepin-selinux-4.4.25-1.el9sat, python-markdown-3.8.2-1.el9pc +6
  • RHSA-2026:14873 Released 2026-05-07 · Red Hat rating Important
    Satellite 6.17.8 Async Update
    • Red Hat Satellite 6.17 for RHEL 9 candlepin-4.4.25-1.el9sat, candlepin-selinux-4.4.25-1.el9sat, python-markdown-3.8.2-1.el9pc +6
  • RHSA-2026:14835 Released 2026-05-07 · Red Hat rating Important
    Satellite 6.18.5 Async Update
    • Red Hat Satellite 6.18 for RHEL 9 python3.12-django-4.2.30-1.el9pc, python3.12-markdown-3.8.2-1.el9pc, python3.12-pyOpenSSL-26.0.0-2.el9pc +1

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Satellite 6AffectedNo fix yet
Red Hat Satellite 6.16 for RHEL 8Fixed RHSA-2026:14874
Red Hat Satellite 6.16 for RHEL 9Fixed RHSA-2026:14874
Red Hat Satellite 6.17 for RHEL 9Fixed RHSA-2026:14873
Red Hat Satellite 6.18 for RHEL 9Fixed RHSA-2026:14835
Not affected: 4 products
  • Red Hat Satellite 6.16 for RHEL 8
  • Red Hat Satellite 6.16 for RHEL 9
  • Red Hat Satellite 6.17 for RHEL 9
  • Red Hat Satellite 6.18 for RHEL 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33176
  2. 2026-10-03 Alias added: GHSA-2j26-frm8-cmj9

References

Patch 3

Advisory 2

Other 5

  • TI-2014-00124 Directory traversal vulnerability in actionpack/lib/abstract_controller/base.rb in the… KEVCVSS 3.1HIGH 7.5
  • TI-2019-03828 Path traversal in Rails https://github.com/rails/rails KEVCVSS 3.1HIGH 7.5
  • TI-2016-00672 Directory traversal vulnerability in Action View in Ruby on Rails before 3.2.22.1, 4.0.x… KEVCVSS 3.1HIGH 7.5
  • TI-2019-03830 Command injection in Rails https://github.com/rails/rails CVSS 3.1CRITICAL 9.8
  • TI-2020-06581 Code injection in https://github.com/rails/rails CVSS 3.1HIGH 8.8
  • TI-2013-00091 active_support/core_ext/hash/conversions.rb in Ruby on Rails before 2.3.15, 3.0.x before… CVSS 2.0HIGH 7.5
See all 117 →

Sources

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