axmail

In axmail

 char username[20];
char fullname[31];
...
        /* Strip SSID */
        if (local) {
                pw = getpwuid(getuid());
        } else {
                strcpy(callsign, call);
                strcpy(username, callsign);
                strlwr(username);
                p = strchr(username, '-');
                if (p) *p = '\0';
                pw = getpwnam(username);
        }
...
                if (local) {
                        strcpy(username, pw->pw_name);
                        strcpy(callsign, username);
                }
                /* Strip full name from the gecos field... */
                if (strchr(pw->pw_gecos, ',') == NULL)
                        strcpy(fullname, pw->pw_gecos);
                else
                        strcpy(fullname, strtok(pw->pw_gecos, ","));

This seems to be a common legacy code bug - assumptions about username/gecos lengths etc.

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