Heap disclosure via unterminated escaped MIME comment
Published Jul 16, 2026 · Updated Jul 16, 2026
Buffer over-read in Cyrus IMAP 3.12.2 and earlier allows remote authenticated users to read adjacent heap data through crafted email. The nested RFC 822 MIME comment parser advances past the message buffer when a comment terminates with an escape backslash, returning heap bytes in parsed output. A valid IMAP account and delivery of the crafted message are required; the demonstrated consequence is limited heap-memory disclosure.
Summary
What happened
Buffer over-read in Cyrus IMAP 3.12.2 and earlier allows remote authenticated users to read adjacent heap data through crafted email. The nested RFC 822 MIME comment parser advances past the message buffer when a comment terminates with an escape backslash, returning heap bytes in parsed output. A valid IMAP account and delivery of the crafted message are required; the demonstrated consequence is limited heap-memory disclosure.
The record
- CVE
- CVE-2026-47088
- Published
- Jul 16, 2026
- Updated
- Jul 16, 2026
- Vendor
- Project Cyrus
- Product
- Cyrus IMAP
- Classifications
- CWE-126
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 16, 2026CVE publishedPublication date reported by the CVE source.
- Jul 16, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <3.12.3
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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