Bug 2501453 (CVE-2026-47081)

Summary: CVE-2026-47081 cyrus-imapd: Cyrus IMAP: Information disclosure of mailbox existence via XAPPLEPUSHSERVICE command
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Cyrus IMAP (cyrus-imapd). An authenticated user could exploit this vulnerability by using the XAPPLEPUSHSERVICE command to determine if specific mailboxes exist on other users' accounts. This could allow the attacker to create Apple Push Notification Service (APNS) notifications for these mailboxes, causing a "mailbox has changed" notice to be pushed to their own device when the mailbox is updated. While no content is leaked, this constitutes an information disclosure regarding the existence and activity of other users' mailboxes.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2501664    
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Description OSIDB Bzimport 2026-07-16 19:01:45 UTC
An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. There is an XAPPLEPUSHSERVICE folder existence oracle and push hijack. An authenticated IMAP user could probe for the existence of arbitrary mailboxes on other users' accounts via the XAPPLEPUSHSERVICE command and then create Apple Push Notification Service notifications for new mail in those mailboxes to their own APNS device. This did not leak any data about the content of mailboxes. Instead, a "mailbox has changed" notice would be pushed when the mailbox modseq changed.