Description
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.
References (2)
Core 2
Scores
CVSS v3
3.1
EPSS
0.0018
EPSS Percentile
7.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-126
Status
published
Products (1)
cyrusimap/Cyrus IMAP
< 3.12.3
Published
Jul 16, 2026
Tracked Since
Jul 17, 2026