5.9
MEDIUM CVSS 3.1
CVE-2026-126351
Addressable: Denial of service in URI path normalization
Description

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.

INFO

Published Date :

Nov. 12, 2026, 10:19 p.m.

Last Modified :

Nov. 12, 2026, 10:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-126351 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Addressable_project addressable
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update Addressable to version 2.9.1 or later to fix path normalization performance.
  • Update the Addressable library to version 2.9.1.
  • Ensure URIs are properly normalized before processing.
  • Avoid processing untrusted URIs if normalization is not needed.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-126351.

URL Resource
https://github.com/sporkmonger/addressable/commit/25c7c412a2f7e06c3cac92872e831f6d053703c5
https://github.com/sporkmonger/addressable/releases/tag/addressable-2.9.1
https://github.com/sporkmonger/addressable/security/advisories/GHSA-qq38-m9mg-xjj5
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-126351 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-126351 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-126351 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-126351 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 12, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-407
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/126xxx/CVE-2026-126351.json">CVE-2026-126351</a>
    Added Reference https://github.com/sporkmonger/addressable/commit/25c7c412a2f7e06c3cac92872e831f6d053703c5
    Added Reference https://github.com/sporkmonger/addressable/releases/tag/addressable-2.9.1
    Added Reference https://github.com/sporkmonger/addressable/security/advisories/GHSA-qq38-m9mg-xjj5
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.