CVE-2026-33169 (GCVE-0-2026-33169)

Vulnerability from cvelistv5 – Published: 2026-03-23 23:07 – Updated: 2026-03-24 15:46
VLAI
Title
Rails Active Support has a possible ReDoS vulnerability in number_to_delimited
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.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-24 15:45 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rails activesupport Affected: >= 8.1.0.beta1, < 8.1.2.1
Affected: >= 8.0.0.beta1, < 8.0.4.1
Affected: < 7.2.3.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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        "assignerShortName": "GitHub_M",
        "cveId": "CVE-2026-33169",
        "datePublished": "2026-03-23T23:07:07.630Z",
        "dateReserved": "2026-03-17T21:17:08.888Z",
        "dateUpdated": "2026-03-24T15:46:43.465Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.