USN-4256-1: Cyrus SASL vulnerability

28 January 2020

cyrus-sasl2 vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 19.10
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 ESM
  • Ubuntu 12.04 ESM


Cyrus SASL could be made to crash or execute arbitrary code if it received a specially crafted LDAP packet.

Software Description

  • cyrus-sasl2 - Cyrus Simple Authentication and Security Layer


It was discovered that Cyrus SASL incorrectly handled certain LDAP packets. An attacker could possibly use this issue to execute arbitrary code or cause a denial of service.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 19.10
libsasl2-2 - 2.1.27+dfsg-1ubuntu0.1
Ubuntu 18.04 LTS
libsasl2-2 - 2.1.27~101-g0780600+dfsg-3ubuntu2.1
Ubuntu 16.04 LTS
libsasl2-2 - 2.1.26.dfsg1-14ubuntu0.2
Ubuntu 14.04 ESM
libsasl2-2 - 2.1.25.dfsg1-17ubuntu0.1~esm1
Ubuntu 12.04 ESM
libsasl2-2 - 2.1.25.dfsg1-3ubuntu0.2

To update your system, please follow these instructions:

After a standard system update you need to restart services using SASL to effect the necessary changes.