CVE-2026-47088
LowCVSS 3.1Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
In cyrus-imapd up to version 3.12.2, a vulnerability was discovered involving heap exposure during parsing of nested MIME comments. An authenticated IMAP user can craft an email message containing an RFC 822 comment ending with a backslash, causing the server to read past the message's end in memory and return heap content.
Risk Assessment
The risk involves potential leakage of sensitive data from server memory, such as other emails, keys, or credentials, which could compromise the confidentiality and integrity of the mail system.
Recommendation
Immediately update cyrus-imapd to version 3.12.3 or later, which includes a fix for this vulnerability. Until the update, restrict IMAP server access to trusted users only.
Original NVD description (English source)
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.