CVE-2026-126350 json
Addressable: Regular Expression Denial of Service in Addressable templates with certain exploded expressions
published 16d ago modified yesterday also EUVD-2026-124730 , GHSA-j82w-28jv-3pmj
- 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 36%
- 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 template expressions using the explode modifier with the slash, dot, semicolon, question-mark, or ampersand operators generate ambiguous regular expressions. When Template#match or Template#extract processes an attacker-controlled URI beginning with the operator's leading character, optional member separators allow catastrophic backtracking and denial of service on MRI Ruby before 3.2 and JRuby. Addressable 2.9.0 incompletely remediated the earlier template issue because its tests did not reach these operator-prefixed paths. 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
- yesterday
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% 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/26d1e9e8409a861571f9d0029022b6e9b9158b5e
web
-
github.com
/sporkmonger/addressable/security/advisories/GHSA-j82w-28jv-3pmj
web, advisory
-
github.com
/sporkmonger/addressable/issues/364
web
-
github.com
/sporkmonger/addressable/releases/tag/addressable-2.9.1
web
-
github.com
/rubysec/ruby-advisory-db/blob/master/gems/addressable/GHSA-j82w-28jv-3pmj.yml
web
-
github.com
/sporkmonger/addressable
package
Sources
- CVE List CVE-2026-126350
- GitHub Advisory GHSA-j82w-28jv-3pmj
- NVD CVE-2026-126350
- Maintainer advisory GHSA-j82w-28jv-3pmj
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.