hfaxd in HylaFAX 4.2.3, when PAM support is disabled, accepts arbitrary passwords, which allows remote attackers to gain privileges.

Multiple eval injection vulnerabilities in HylaFAX 4.2.3 and earlier allow remote attackers to execute arbitrary commands via (1) the notify script in HylaFAX 4.2.0 to 4.2.3 and (2) crafted CallID parameters to the faxrcvd script in HylaFAX 4.2.2 and 4.2.3.

xferfaxstats in HylaFax 4.2.1 and earlier allows local users to overwrite arbitrary files via a symlink attack on the xferfax$$ temporary file.

hfaxd in HylaFAX before 4.2.1, when installed with a "weak" hosts.hfaxd file, allows remote attackers to authenticate and bypass intended access restrictions via a crafted (1) username or (2) hostname that satisfies a regular expression that is matched against a hosts.hfaxd entry without a password.