CVE-2026-33176

Description

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.

CVSS Metrics

• v4.0•MEDIUM•Score: 6.6CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
• v4.0•MEDIUM•Score: 6.6CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
• v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.84%• Percentile: 56%

Techniques & Countermeasures

• CWE-400•Uncontrolled Resource Consumption

  The product does not properly control the allocation and maintenance of a limited resource.

• CWE-770•Allocation of Resources Without Limits or Throttling

  The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

Affected Systems

• chainguard•cinc-auditor

  < 7.0.107-r1

• chainguard•gitlab-rails-ce-18.1

  all

• chainguard•gitlab-rails-ce-18.10

  < 18.10.3-r1

• chainguard•gitlab-rails-ce-18.2

  all

• chainguard•gitlab-rails-ce-18.3

  all

• chainguard•gitlab-rails-ce-18.4

  all

• chainguard•gitlab-rails-ce-18.5

  all

• chainguard•gitlab-rails-ce-18.6

  all

• chainguard•gitlab-rails-ce-18.7

  all

• chainguard•gitlab-rails-ce-18.8

  < 18.8.11-r4

• chainguard•gitlab-rails-ce-18.9

  < 18.9.5-r0

• chainguard•gitlab-rails-ce-fips-18.1

  all

• chainguard•gitlab-rails-ce-fips-18.10

  < 18.10.3-r0

• chainguard•gitlab-rails-ce-fips-18.2

  all

• chainguard•gitlab-rails-ce-fips-18.3

  all

• chainguard•gitlab-rails-ce-fips-18.4

  all

• chainguard•gitlab-rails-ce-fips-18.5

  all

• chainguard•gitlab-rails-ce-fips-18.6

  all

• chainguard•gitlab-rails-ce-fips-18.7

  all

• chainguard•gitlab-rails-ce-fips-18.8

  all

• chainguard•gitlab-rails-ce-fips-18.9

  < 18.9.5-r0

• chainguard•kube-fluentd-operator

  < 1.18.2-r60

• chainguard•kube-logging-operator-fluentd-outputs

  < 6.4.0-r9

• chainguard•ruby3.2-rails-7.1

  all

• chainguard•ruby3.2-rails-8.1

  < 8.1.3-r0

• chainguard•ruby3.3-rails-7.1

  all

• chainguard•ruby3.4-rails-7.1

  all

• chainguard•ruby3.4-rails-8.0

  < 8.0.5-r0

• chainguard•ruby4.0-rails-7.1

  all

• wolfi•cinc-auditor

  < 7.0.107-r1

• wolfi•kube-fluentd-operator

  < 1.18.2-r60

• wolfi•kube-logging-operator-fluentd-outputs

  < 6.4.0-r9

• wolfi•ruby3.2-rails-8.1

  < 8.1.3-r0

• debian•rails

  all | all | all | < 2:7.2.3.1+dfsg-1

• rails•activesupport

  ≥ 8.1.0.beta1, < 8.1.2.1 | ≥ 8.0.0.beta1, < 8.0.4.1 | < 7.2.3.1

• rubyonrails•rails

  < 7.2.3.1 | ≥ 8.0.0, < 8.0.4.1 | ≥ 8.1.0, < 8.1.2.1

References (10)

• https://github.com/rails/rails/security/advisories/GHSA-2j26-frm8-cmj9
• https://github.com/rails/rails/commit/19dbab51ca086a657bb86458042bc44314916bcb
• https://github.com/rails/rails/commit/ebd6be18120d1136511eb516338e27af25ac0a1a
• https://github.com/rails/rails/commit/ee2c59e730e5b8faed502cd2c573109df093f856
• https://github.com/rails/rails/releases/tag/v7.2.3.1
• https://github.com/rails/rails/releases/tag/v8.0.4.1
• https://github.com/rails/rails/releases/tag/v8.1.2.1
• https://security-tracker.debian.org/tracker/CVE-2026-33176
• https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33176.json
• https://nvd.nist.gov/vuln/detail/CVE-2026-33176