Netatalk 2.1.0 through 4.4.2 combines multiple errno values using bitwise OR, resulting in incorrect error codes when multiple error conditions occur simultaneously, which may allow a remote attacker to cause a minor service disruption via conditions that trigger incorrect error-handling paths.
A missing break statement in DSI OpenSession processing in Netatalk 1.5.0 through 4.4.2 causes a DSIOPT_ATTNQUANT switch case to fall through into DSIOPT_SERVQUANT, resulting in unintended session option handling that may allow a remote attacker to cause a minor service disruption via crafted DSI session options.