CVE-2026-126352 json
Addressable: Regular Expression Denial of Service in Addressable templates with multiple variables
published 16d ago modified yesterday also EUVD-2026-124732 , GHSA-9f42-57jx-vpp3
- cvss
- 5.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 37%
- public exploits
- 0
- none known
Summary
Addressable is an alternative implementation to the URI implementation that is part of Ruby's standard library. From 2.3.0 until 2.9.1, URI templates with several variables in one expression or several adjacent expressions generate ambiguous regular expressions. Affected forms include multi-variable expressions using operators other than plus and number sign, large plus or number-sign expressions, and adjacent single-variable expressions. Template#match or Template#extract can backtrack polynomially or exponentially on attacker-controlled URIs, causing denial of service on MRI Ruby before 3.2 and JRuby, with the large plus and number-sign form also affecting MRI Ruby 3.2 and TruffleRuby 40.0. URI parsing and Template#expand are unaffected. This issue is fixed in version 2.9.1.
Patch / fix
- rubygems addressable 2.9.1
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2d ago
Exploit prediction
0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-14).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| rubygems | addressable | >=2.3.0, <2.9.1 |
2.9.1 |
Affected products
- sporkmonger addressable
Classification
- Weakness
-
- CWE-1333 Inefficient Regular Expression Complexity
References
-
github.com
/sporkmonger/addressable/commit/f2b27b3ab252e56b3fa3519f7ebb491d54cf7b7c
web
-
github.com
/sporkmonger/addressable/security/advisories/GHSA-9f42-57jx-vpp3
web, advisory
-
github.com
/sporkmonger/addressable/releases/tag/addressable-2.9.1
web
-
github.com
/rubysec/ruby-advisory-db/blob/master/gems/addressable/GHSA-9f42-57jx-vpp3.yml
web
-
github.com
/sporkmonger/addressable
package
Sources
- CVE List CVE-2026-126352
- GitHub Advisory GHSA-9f42-57jx-vpp3
- NVD CVE-2026-126352
- Maintainer advisory GHSA-9f42-57jx-vpp3
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of sporkmonger/addressable published their own advisory on GitHub. Reviewed sources take precedence over it.