Bug 2525149

Summary: CVE-2026-79772 rubygem-nokogiri: Nokogiri: Signature validation bypass via unchecked return value [fedora-all]
Product: [Fedora] Fedora Reporter: Joel Chamberlain <jochambe>
Component: rubygem-nokogiriAssignee: Mamoru TASAKA <mtasaka>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: mtasaka, pvalena, vondruch
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["f8a56247-79b0-408d-99d4-221b91e7dbea"]}
Fixed In Version: Doc Type: ---
Doc Text:
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Clone Of: Environment:
Last Closed: 2026-08-28 12:47:23 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2523567    

Description Joel Chamberlain 2026-08-27 18:24:50 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

Nokogiri versions before 1.19.1 fail to check the return value from xmlC14NExecute in the canonicalize method, returning an empty string on failure instead of raising an exception. Attackers can exploit this to bypass signature validation in downstream SAML libraries by providing invalid canonicalized XML that is incorrectly accepted as valid.