CVE-2026-33169

Summary

Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. NumberToDelimitedConverter uses a lookahead-based regular expression with gsub! to insert thousands delimiters. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, the interaction between the repeated lookahead group and gsub! can produce quadratic time complexity on long digit strings. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Affected Software

VendorProductVersion RangeStatus
railsactivesupport>= 8.1.0.beta1, < 8.1.2.1affected
railsactivesupport>= 8.0.0.beta1, < 8.0.4.1affected
railsactivesupport< 7.2.3.1affected

Weaknesses

  • CWE-400: CWE-400: Uncontrolled Resource Consumption
  • CWE-1333: CWE-1333: Inefficient Regular Expression Complexity

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References