# CVE-2026-126351: Addressable: Denial of service in URI path normalization

Status: published. Published: 2026-11-12. Updated: 2026-11-12.

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.

## Remediation

- fix: addressable (RubyGems): OSV reports a fixed version 2.9.1. Check the advisory for supported release branches. (source: OSV GHSA-qq38-m9mg-xjj5) — https://github.com/advisories/GHSA-qq38-m9mg-xjj5

## Affected products and versions

- sporkmonger / addressable: < 2.9.1 (affected). Source: CNA: GitHub_M
-  / addressable (addressable): 0.1.0 (affected, RubyGems); 0.1.1 (affected, RubyGems); 0.1.2 (affected, RubyGems); 1.0.0 (affected, RubyGems); 1.0.1 (affected, RubyGems); 1.0.2 (affected, RubyGems); 1.0.3 (affected, RubyGems); 1.0.4 (affected, RubyGems); 2.0.0 (affected, RubyGems); 2.0.1 (affected, RubyGems); 2.0.2 (affected, RubyGems); 2.1.0 (affected, RubyGems); 2.1.1 (affected, RubyGems); 2.1.2 (affected, RubyGems); 2.2.0 (affected, RubyGems); 2.2.1 (affected, RubyGems); 2.2.2 (affected, RubyGems); 2.2.3 (affected, RubyGems); 2.2.4 (affected, RubyGems); 2.2.5 (affected, RubyGems); 2.2.6 (affected, RubyGems); 2.2.7 (affected, RubyGems); 2.2.8 (affected, RubyGems); 2.3.2 (affected, RubyGems); 2.3.3 (affected, RubyGems); 2.3.4 (affected, RubyGems); 2.3.5 (affected, RubyGems); 2.3.6 (affected, RubyGems); 2.3.7 (affected, RubyGems); 2.3.8 (affected, RubyGems); 2.4.0 (affected, RubyGems); 2.5.0 (affected, RubyGems); 2.5.1 (affected, RubyGems); 2.5.2 (affected, RubyGems); 2.6.0 (affected, RubyGems); 2.7.0 (affected, RubyGems); 2.8.0 (affected, RubyGems); 2.8.1 (affected, RubyGems); 2.8.10 (affected, RubyGems); 2.8.2 (affected, RubyGems); 2.8.3 (affected, RubyGems); 2.8.4 (affected, RubyGems); 2.8.5 (affected, RubyGems); 2.8.6 (affected, RubyGems); 2.8.7 (affected, RubyGems); 2.8.8 (affected, RubyGems); 2.8.9 (affected, RubyGems); 2.9.0 (affected, RubyGems); Ecosystem version events: introduced 0; fixed 2.9.1. Source: OSV GHSA-qq38-m9mg-xjj5

## Severity and prioritization

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: GitHub_M

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: security-advisories@github.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-407

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/sporkmonger/addressable/security/advisories/GHSA-qq38-m9mg-xjj5 (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/sporkmonger/addressable/commit/25c7c412a2f7e06c3cac92872e831f6d053703c5 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/sporkmonger/addressable/releases/tag/addressable-2.9.1 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/sporkmonger/addressable/commit/25c7c412a2f7e06c3cac92872e831f6d053703c5 (security-advisories@github.com)

- https://github.com/sporkmonger/addressable/releases/tag/addressable-2.9.1 (security-advisories@github.com)

- https://github.com/sporkmonger/addressable/security/advisories/GHSA-qq38-m9mg-xjj5 (security-advisories@github.com)

- https://github.com/advisories/GHSA-qq38-m9mg-xjj5 (OSV / GitHub Security Advisories; advisory)

- https://osv.dev/vulnerability/GHSA-qq38-m9mg-xjj5 (OSV / GitHub Security Advisories; osv)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-126351; retrieved 2026-11-12; source updated 2026-11-12

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-126351; retrieved 2026-11-13; source updated 2026-11-12

- OSV / GitHub Security Advisories: https://osv.dev/vulnerability/GHSA-qq38-m9mg-xjj5; retrieved 2026-11-12; source updated 2026-11-12

Revision: 2f16bb602a1f12834347a7689e81a12225f060502911e55042b43a988b3eedad

Canonical: https://y2.dev/cve/CVE-2026-126351

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