RubySec

Providing security resources for the Ruby community

CVE-2023-22796 (activesupport): ReDoS based DoS vulnerability in Active Support’s underscore

ADVISORIES

GEM

activesupport

FRAMEWORK

Ruby on Rails

PATCHED VERSIONS

  • ~> 5.2.8, >= 5.2.8.15
  • ~> 6.1.7, >= 6.1.7.1
  • >= 7.0.4.1

DESCRIPTION

There is a possible regular expression based DoS vulnerability in Active Support. This vulnerability has been assigned the CVE identifier CVE-2023-22796.

Versions Affected: All Not affected: None Fixed Versions: 5.2.8.15 (Rails LTS), 6.1.7.1, 7.0.4.1

Impact

A specially crafted string passed to the underscore method can cause the regular expression engine to enter a state of catastrophic backtracking. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability.

This affects String#underscore, ActiveSupport::Inflector.underscore, String#titleize, and any other methods using these.

All users running an affected release should either upgrade or use one of the workarounds immediately.

Workarounds

There are no feasible workarounds for this issue.

Users on Ruby 3.2.0 or greater may be able to reduce the impact by configuring Regexp.timeout.