Input validation error in Dovecot - CVE-2019-10691
Published: April 18, 2019
Vulnerability identifier: #VU18307
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2019-10691
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform denial of service (DoS) attack.
The vulnerability exists due to improper input validation of user-supplied characters in UTF-8 encoding within the JSON encoder. A remote unauthenticated attacker can supply a specially crafted string that contains invalid UTF-8 characters via a username during authentication process or via “From” or “Subject” headers in an email (if OX push notification driver is enabled) and crash the affected server.
Successful exploitation of the vulnerability will result in denial of service (DoS) attack.
Affected software
Dovecot
Gentoo Linux
Arch Linux
Opensuse
Fedora
dovecot (Alpine package)
dovecot (Ubuntu package)
dovecot
Gentoo Linux
Arch Linux
Opensuse
Fedora
dovecot (Alpine package)
dovecot (Ubuntu package)
dovecot
How to mitigate CVE-2019-10691
Install updates from vendor's website.
Dovecot - update to 2.3.5.2
dovecot (Alpine package) - update to 2.3.6-r0
dovecot (Ubuntu package) - addressed in versions 1:2.3.2.1-1ubuntu3.3, 1:2.3.4.1-1ubuntu2.1
dovecot - update to 2.3.6-3.fc29
dovecot (Alpine package) - update to 2.3.6-r0
dovecot (Ubuntu package) - addressed in versions 1:2.3.2.1-1ubuntu3.3, 1:2.3.4.1-1ubuntu2.1
dovecot - update to 2.3.6-3.fc29