CVE-2026-126352

Addressable: Regular Expression Denial of Service in Addressable templates with multiple variables

Published Nov 12, 2026 CVSS 3.1 · 5.9 Medium EPSS n/a KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-9f42-57jx-vpp3 Addressable: Regular Expression Denial of Service in templates with multiple variables
History
Type Values Removed Values Added
Description 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.
Title Addressable: Regular Expression Denial of Service in Addressable templates with multiple variables
Weaknesses CWE-1333
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Subscriptions

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Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Nov 13, 2026, 12:35 AM
Reserved
Nov 10, 2026, 9:12 PM
Status
Received
Published
Nov 12, 2026, 10:19 PM
Modified
Nov 13, 2026, 2:18 AM