The speedtouch package contains a driver for the ADSL SpeedTouch USB modem.
The Speedtouch USB driver contains multiple format string vulnerabilities in modem_run, pppoa2 and pppoa3. This flaw is due to an improperly made syslog() system call.
A malicious local user could exploit this vulnerability by causing a buffer overflow, and potentially allowing the execution of arbitrary code with escalated privileges.
There is no known workaround at this time.
All Speedtouch USB driver users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-dialup/speedtouch-1.3.1"