Bug 2450556 (CVE-2026-33169)

Summary: CVE-2026-33169 rails: rails-activesupport: Active Support: Denial of Service via crafted long digit strings
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: anthomas, ehelms, ggainey, juwatts, mhulan, nmoumoul, osousa, pcreech, rchan, smallamp, tmalecek
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Active Support, a toolkit of support libraries for the Rails framework. The `NumberToDelimitedConverter` component, responsible for formatting numbers, uses a regular expression that can lead to a significant slowdown when processing unusually long digit strings. A remote attacker could exploit this by providing specially crafted input, potentially causing a Denial of Service (DoS) due by consuming excessive system resources.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-03-24 00:02:54 UTC
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.