CVE-2026-33176 (GCVE-0-2026-33176)
Vulnerability from cvelistv5 – Published: 2026-03-23 23:29 – Updated: 2026-03-24 18:42
VLAI
EPSS
VEX
Title
Rails Active Support has a possible DoS vulnerability in its number helpers
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-24 18:42 UTC
CWE
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://github.com/rails/rails/security/advisorie… | x_refsource_CONFIRM |
| https://github.com/rails/rails/commit/19dbab51ca0… | x_refsource_MISC |
| https://github.com/rails/rails/commit/ebd6be18120… | x_refsource_MISC |
| https://github.com/rails/rails/commit/ee2c59e730e… | x_refsource_MISC |
| https://github.com/rails/rails/releases/tag/v7.2.3.1 | x_refsource_MISC |
| https://github.com/rails/rails/releases/tag/v8.0.4.1 | x_refsource_MISC |
| https://github.com/rails/rails/releases/tag/v8.1.2.1 | x_refsource_MISC |
Impacted products
1 product
| 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 |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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 |
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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.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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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.
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