CVE-2024-23185

描述

Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger mails though, allowing them to DoS themselves (although maybe cause some memory issues for the backend in general). One can implement restrictions on headers on MTA component preceding Dovecot. No publicly available exploits are known.

如何修補 CVE-2024-23185

要修補 CVE-2024-23185,請將受影響套件升級到下列已修補版本。

• —升級至 2.3.21.1-r0 或更新版本
• —升級至 1:2.3.13+dfsg1-2+deb11u2 或更新版本

CVE-2024-23185 正在被利用嗎?

低 — EPSS 為 1.3%,目前沒有觀察到大規模利用活動。

受影響套件(2)

• from 0, < 2.3.21.1-r0
• from 0, < 1:2.3.13+dfsg1-2+deb11u2

CVSS 分數

參考連結(2)

• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2024-23185
• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2024-23185