# CVE-2026-33169: rails: Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework

CVE-2026-33169 is fixed in rails on 1 platform, first by DEBIAN-CVE-2026-33169, released March 24, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-33169
- Priority: Routine
- CVSS: 5.3 (medium)
- EPSS: 0.0066
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 24, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | rails Debian 12.15 (bookworm) | 2:6.1.7.10+dfsg-1~deb12u3 | [DEBIAN-CVE-2026-33169](https://patchblox.com/security/data/fix/linux/debian-cve-2026-33169.md) | Mar 24, 2026 |
| Linux | rails Debian 13.5 (trixie) | 2:7.2.2.2+dfsg-2~deb13u2 | [DEBIAN-CVE-2026-33169](https://patchblox.com/security/data/fix/linux/debian-cve-2026-33169.md) | Mar 24, 2026 |
| Linux | rails Debian 14 | 2:7.2.3.1+dfsg-1 | [DEBIAN-CVE-2026-33169](https://patchblox.com/security/data/fix/linux/debian-cve-2026-33169.md) | Mar 24, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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