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.
https://github.com/rails/rails/security/advisories/GHSA-2j26-frm8-cmj9
https://github.com/rails/rails/releases/tag/v8.1.2.1
https://github.com/rails/rails/releases/tag/v8.0.4.1
https://github.com/rails/rails/releases/tag/v7.2.3.1
https://github.com/rails/rails/commit/ee2c59e730e5b8faed502cd2c573109df093f856
https://github.com/rails/rails/commit/ebd6be18120d1136511eb516338e27af25ac0a1a
https://github.com/rails/rails/commit/19dbab51ca086a657bb86458042bc44314916bcb
Published: 2026-03-24
Updated: 2026-03-24
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 8.7
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00016