CVE-2017-14461

An attacker can trigger this vulnerability by sending a specially crafted email over SMTP to a Dovecot server. The email must contain malformed address fields, such as those with unbalanced parentheses or unclosed brackets within quoted strings or domain literals. When Dovecot's MTA passes this email to the parser, functions like `rfc822_skip_comment`, `rfc822_parse_domain_literal`, or `rfc822_parse_quoted_string` can be invoked with invalid context, leading to an out-of-bounds read [ref_id=1].

The vulnerability resides in the RFC822 parser implementation within Dovecot. Specifically, the functions `rfc822_skip_comment`, `rfc822_parse_domain_literal`, and `rfc822_parse_quoted_string` are identified as being susceptible to triggering an out-of-bounds read due to improper handling of input data [ref_id=1]. The issue stems from how the parser increments its data pointer without sufficient checks against buffer boundaries.

The advisory does not specify a patch or provide details on how the vulnerability is fixed. However, it indicates that the issue lies within the RFC822 parser's handling of email addresses, specifically in functions like `rfc822_skip_comment`, `rfc822_parse_domain_literal`, and `rfc822_parse_quoted_string` [ref_id=1]. A fix would likely involve adding boundary checks to prevent the parser from reading beyond allocated memory buffers.