CVE-2024-23184

Publication date 24 August 2024

Last updated 16 September 2024


Ubuntu priority

Having a large number of address headers (From, To, Cc, Bcc, etc.) becomes excessively CPU intensive. With 100k header lines CPU usage is already 12 seconds, and in a production environment we observed 500k header lines taking 18 minutes to parse. Since this can be triggered by external actors sending emails to a victim, this is a security issue. An external attacker can send specially crafted messages that consume target system resources and cause outage. One can implement restrictions on address headers on MTA component preceding Dovecot. No publicly available exploits are known.

Read the notes from the security team

Status

Package Ubuntu Release Status
dovecot 24.04 LTS noble
Fixed 1:2.3.21+dfsg1-2ubuntu6
22.04 LTS jammy
Fixed 1:2.3.16+dfsg1-3ubuntu2.4
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes


mdeslaur

introduced in 2.3.10 by: https://github.com/dovecot/core/commit/469fcd3bdd7df40bb8f4d131121f3bfbceade02a

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
dovecot

References

Related Ubuntu Security Notices (USN)

    • USN-6982-1
    • Dovecot vulnerabilities
    • 2 September 2024
    • USN-7013-1
    • Dovecot vulnerabilities
    • 16 September 2024

Other references