CVE-2026-33169
MEDIUM5.3EPSS 0.02%Rails Active Support has a possible ReDoS vulnerability in number_to_delimited
Published: 3/23/2026Modified: 5/13/2026
Description
### Impact `NumberToDelimitedConverter` used a regular expression with `gsub!` to insert thousands delimiters. This could produce quadratic time complexity on long digit strings. ### Releases The fixed releases are available at the normal locations. ### Credit This issue was responsibly reported by Hackerone researcher [scyoon](https://hackerone.com/scyoon).
Affected packages (2)
- Debian/railsfrom 0
- RubyGems/activesupport>= 8.1.0.beta1, < 8.1.2.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
References (11)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-33169
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2026-33169
- PATCHhttps://github.com/rails/rails
- WEBhttps://github.com/rails/rails/commit/29154f1097da13d48fdb3200760b3e3da66dcb11
- WEBhttps://github.com/rails/rails/commit/b54a4b373c6f042cab6ee2033246b1c9ecc38974
- WEBhttps://github.com/rails/rails/commit/ec1a0e215efd27a3b3911aae6df978a80f456a49
- WEBhttps://github.com/rails/rails/releases/tag/v7.2.3.1
- WEBhttps://github.com/rails/rails/releases/tag/v8.0.4.1
- WEBhttps://github.com/rails/rails/releases/tag/v8.1.2.1
- WEBhttps://github.com/rails/rails/security/advisories/GHSA-cg4j-q9v8-6v38
- WEBhttps://github.com/rubysec/ruby-advisory-db/blob/master/gems/activesupport/CVE-2026-33169.yml