CVE-2026-126354

MEDIUM
Published Nov 12, 2026 CWE-22 CWE-436

Description

Addressable is an alternative implementation to the URI implementation that is part of Ruby's standard library. From 2.2.5 until 2.9.1, Addressable::URI.normalize_path can resolve a path containing leading parent segments and later parent segments to a different path than an RFC 3986 resolver. URI#normalize, URI#join, URI#==, and URI#=== inherit the result. An application that authorizes the Addressable-normalized path but sends the original URI to another resolver can allow access outside the intended path allowlist. Applications that use the same normalized value for authorization and the request, or reject parent segments, are unaffected. This issue is fixed in version 2.9.1.

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CVSS v3.1 Score

4.8
MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Weakness Type (CWE)

CWE-22 Path Traversal
CWE-436 CWE-436

References

Frequently Asked Questions

What is CVE-2026-126354? +
Addressable is an alternative implementation to the URI implementation that is part of Ruby's standard library. From 2.2.5 until 2.9.1, Addressable::URI.normalize_path can resolve a path containing leading parent segments and later parent segments to a different path than an RFC 3986 resolver. URI#normalize, URI#join, URI#==, and URI#=== inherit the result. An application that authorizes the Addressable-normalized path but sends the original URI to another resolver can allow access outside the intended path allowlist. Applications that use the same normalized value for authorization and the request, or reject parent segments, are unaffected. This issue is fixed in version 2.9.1. It has a CVSS v3.1 base score of 4.8 (MEDIUM).
How severe is CVE-2026-126354? +
CVE-2026-126354 has a CVSS v3.1 score of 4.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
How do I check if I'm vulnerable to CVE-2026-126354? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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