CVE-2026-33176

High

Description

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.

SeverityHigh
CVSS7.5
Exploit probability—
ProductRails
PublishedMar 24, 2026
First seenMar 24, 2026

How to fix

Update
  • rubyonrails rails7.2.3.1, 8.0.4.1, 8.1.2.1 or later

Affected products

ProductAffected versionsFixed in
rubyonrails railsv < 7.2.3.1, 8.0.0 ≤ v < 8.0.4.1, 8.1.0 ≤ v < 8.1.2.17.2.3.1, 8.0.4.1, 8.1.2.1

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CVE-2026-33176 · Rails · Dark Radar