Bug 2501663

Summary: CVE-2026-47088 cyrus-imapd: Cyrus IMAP: Information disclosure via heap exposure in MIME comment parsing [fedora-all]
Product: [Fedora] Fedora Reporter: Ganesh <gnaik>
Component: cyrus-imapdAssignee: Martin Osvald 🛹 <mosvald>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: low Docs Contact:
Priority: low    
Version: rawhideCC: fhrdina, jorton, j, mosvald, pavel, zdohnal
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["ccef2467-0b17-4020-aa82-e6f8794a75de"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2501455    

Description Ganesh 2026-07-17 03:42:07 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.

An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. There is heap exposure in nested MIME comment parsing. An authenticated IMAP user could craft an email message containing an RFC 822 comment ending with a backslash. When parsing the message, the server would read past the message's end in memory, and read into the heap, returning the read content to the user.