There are 2 open security issues in bookworm.
1 important issue:
- CVE-2026-67194:
Courier IMAP before 6.0.1 and Courier Mail Server before 2.0.2 allow authenticated IMAP users to crash the imapd process via deeply nested parenthesized SEARCH queries. The SEARCH command parser (alloc_search_key in searchinfo.C) recursively descends on nested parenthesized groups through a mutual recursion chain with alloc_search_andlist() and alloc_search_notkey(), with no depth limit. Courier IMAP has no overall command line length limit, making exploitation trivial. A single IMAP command with ~2500 nested parentheses overflows the 8MB default stack, causing SIGSEGV.
1 issue left for the package maintainer to handle:
- CVE-2021-38084:
(needs triaging)
An issue was discovered in the POP3 component of Courier Mail Server before 1.1.5. Meddler-in-the-middle attackers can pipeline commands after the POP3 STLS command, injecting plaintext commands into an encrypted user session.
You can find information about how to handle this issue in the security team's documentation.
![[bug history graph]](https://qa.debian.org/data/bts/graphs/c/courier.png){kind=link}