CVE-2017-2669 Denial of service in dovecot
Attackers can cause denial of service in Dovecot by sending crafted variables during authentication when dict passdb/userdb is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2017-2669?
CVE-2017-2669 is a low-severity denial of service vulnerability in Debian Debian Linux, published on 21 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Dovecot before version 2.2.29 is vulnerable to a denial of service. When 'dict' passdb and userdb were used for user authentication, the username sent by the IMAP/POP3 client was sent through var_expand() to perform %variable expansion. Sending specially crafted %variable fields could result in excessive memory usage causing the process to crash (and restart), or excessive CPU usage causing all authentications to hang.
Weakness: CWE-20
Which versions are affected by CVE-2017-2669?
It affects 2 products.
Linux distribution packages (12)
dovecot SUSE:Linux Enterprise Server 12 SP1 | All versions | 2.2-3.1 |
dovecot22 SUSE:Linux Enterprise Server 12 SP1 | All versions | 2.2.29.1-11.1 |
dovecot SUSE:Linux Enterprise Server 12 SP2 | All versions | 2.2-3.1 |
dovecot22 SUSE:Linux Enterprise Server 12 SP2 | All versions | 2.2.29.1-11.1 |
dovecot SUSE:Linux Enterprise Server for Raspberry Pi 12 SP2 | All versions | 2.2-3.1 |
dovecot22 SUSE:Linux Enterprise Server for Raspberry Pi 12 SP2 | All versions | 2.2.29.1-11.1 |
dovecot SUSE:Linux Enterprise Server for SAP Applications 12 SP1 | All versions | 2.2-3.1 |
dovecot22 SUSE:Linux Enterprise Server for SAP Applications 12 SP1 | All versions | 2.2.29.1-11.1 |
dovecot SUSE:Linux Enterprise Server for SAP Applications 12 SP2 | All versions | 2.2-3.1 |
dovecot22 SUSE:Linux Enterprise Server for SAP Applications 12 SP2 | All versions | 2.2.29.1-11.1 |
dovecot22 SUSE:Linux Enterprise Software Development Kit 12 SP1 | All versions | 2.2.29.1-11.1 |
dovecot22 SUSE:Linux Enterprise Software Development Kit 12 SP2 | All versions | 2.2.29.1-11.1 |
Products include Debian Debian Linux, Dovecot Dovecot.
How do I fix CVE-2017-2669?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2017-2669 being exploited?
There is no known exploitation of CVE-2017-2669 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as DEBIAN-CVE-2017-2669, GHSA-qchv-9m57-q82h, SUSE-SU-2017:1250-1, USN-3258-1, USN-3258-2.