CVE-2026-126351 json
Addressable: Denial of service in URI path normalization
published 16d ago modified yesterday also EUVD-2026-124731 , GHSA-qq38-m9mg-xjj5
- 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 35%
- public exploits
- 0
- none known
Summary
Addressable is an alternative implementation to the URI implementation that is part of Ruby's standard library. Prior to 2.9.1, Addressable::URI.normalize_path repeatedly scans and rewrites paths while removing only one nested dot segment per pass, producing quadratic work. URI#normalize, URI#normalized_path, URI#join, URI#==, and URI#=== inherit the behavior, so processing a sufficiently long attacker-controlled URI can consume a worker thread and cause denial of service on every Ruby implementation. URI.parse alone and code that never normalizes, compares, or joins untrusted URIs are unaffected. This issue is fixed in version 2.9.1.
Patch / fix
- rubygems addressable 2.9.1
Is CVE-2026-126351 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- yesterday
Exploit prediction
0.41% chance of exploitation in the next 30 days, higher than 35% 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 | <2.9.1 |
2.9.1 |
Affected products
- sporkmonger addressable
Classification
- Weakness
-
- CWE-407 Inefficient Algorithmic Complexity
References
-
github.com
/sporkmonger/addressable/commit/25c7c412a2f7e06c3cac92872e831f6d053703c5
web
-
github.com
/sporkmonger/addressable/security/advisories/GHSA-qq38-m9mg-xjj5
web, advisory
-
github.com
/sporkmonger/addressable/releases/tag/addressable-2.9.1
web
-
github.com
/rubysec/ruby-advisory-db/blob/master/gems/addressable/GHSA-qq38-m9mg-xjj5.yml
web
-
github.com
/sporkmonger/addressable
package
Sources
- CVE List CVE-2026-126351
- GitHub Advisory GHSA-qq38-m9mg-xjj5
- NVD CVE-2026-126351
- Maintainer advisory GHSA-qq38-m9mg-xjj5
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.