Bug 2536089 (CVE-2026-92598)

Summary: CVE-2026-92598 nodemailer: Nodemailer: Domain allow-list bypass via improper international domain name encoding
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: abarbaro, alizardo, dschmidt, jchui, jhe, jlanda, kaycoth, kshier, ktsao, lchilton, nboldt, oaljalju, psrna, rbobbitt, rhel-process-autobot, sfeifer, simaishi, stcannon, teagle, watson-tool-maintainers, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Nodemailer. This vulnerability arises from the failure to properly apply UTS-46 normalization when encoding international domain names. A remote attacker can exploit this by crafting recipient addresses with invisible characters or compatibility mappings. This allows them to bypass domain allow-list checks, leading to emails being delivered to attacker-controlled domains via SMTP.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-17 15:03:54 UTC 
Nodemailer before 9.1.0 fails to apply UTS-46 normalization when encoding international domain names, causing the domain resolver to compute a different Punycode A-label than standards-compliant parsers. Attackers can craft recipient addresses with invisible characters or compatibility mappings that pass domain allow-list checks but are delivered to attacker-controlled domains via SMTP.