Rails Active Support has a possible DoS vulnerability in its number helpers — CVE-2026-33176

Summary

### Impact Active Support number helpers accept strings containing scientific notation (e.g. `1e10000`), which when converted to a string could be expanded 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. ### Releases The fixed releases are available at the normal locations.…

Product

rubygems: activesupport

What to do

General, cautious steps (verify details in the official source):

• Review exposure and plan remediation based on risk and environment.
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

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