Wi-Fi security issues at free hot spots?

Archived from groups: alt.internet.wireless (More info?)

How can I improve my Wi-Fi security when surfing at free hot spots,
which exist at my local library and also on my local university
campus?

I do have a firewall installed on my laptop and only use HTTPS sites
for credit card, bank, etc info. However my email is HTTP.

any info is appreciated

thanks
5 answers Last reply
More about security issues free spots
  1. Archived from groups: alt.internet.wireless (More info?)

    billpritjr@spamhole.com (Bill) wrote in news:15b4be0.0406192059.6526e559
    @posting.google.com:

    > How can I improve my Wi-Fi security when surfing at free hot spots,
    > which exist at my local library and also on my local university
    > campus?
    >
    > I do have a firewall installed on my laptop and only use HTTPS sites
    > for credit card, bank, etc info. However my email is HTTP.
    >
    > any info is appreciated


    It seems that you're doing a lot of *right* things. I have never used a
    public hot spot. But if I do, I want to have a *clue*.

    The WatchGuard article on HOT Spots and security has helped in my
    understanding the security risks.

    HTH

    Duane :)

    <snip>

    Hot Spot or Hot Zone?
    Understanding the Hazards of Public WiFi LANs
    By David Piscitello, President, Core Competence

    Its presence is spreading. Order a cup of coffee, or a burger, then use
    WiFi to surf the 'net. Waiting for a delayed flight? Use WiFi to surf the
    'net. Relaxing poolside in a luxury hotel when seized by the urge to IM
    your buddy? Use WiFi to surf the 'net.

    Internet access via a public Wireless LAN, also known as a hotspot, is
    available nearly everywhere, and it's easy to access. Most hotspots are
    reasonably priced: many are free, or free with other purchase from the
    franchising merchant. Some hotspot operators (Boingo, for example) even
    provide client software that identifies WiFi signals of locations that
    offer their Hotspot services. The catch? WiFi hotspots can be hot zones
    for unsuspecting end users and unprotected laptops and handheld devices.

    How a Hotspot can become a Hot Zone
    A hot zone is a danger area due to biological, chemical, or nuclear
    contamination. Areas like Chernobyl and Love Canal became hot zones
    because safeguards against contamination were inadequate or non-existent.
    A wireless hotspot, too, may offer no or inadequate safeguards to protect
    users against:

    Viruses and other malware
    Denial of service attacks
    Attacks against services you run (e.g., Microsoft file sharing, Web, ftp,
    Instant and even Short Messaging Services)
    ARP poisoning, and
    Various hijacking and phishing attacks.
    First rule of thumb for safer public WiFi use: treat a hotspot as an
    untrusted network. Protect your laptop or handheld from attack by
    installing and maintaining antivirus and personal firewall software.
    Otherwise, viruses may be transmitted to an open file share over a
    hotspot network, maliciously or benignly, and then to you. You also risk
    infection if the hotspot operator doesn't prevent station-to-station
    connections: certain viruses and blended threats try to propagate using
    network and file sharing services.

    Personal firewalls are especially important if the WiFi service you use
    assigns you a public IP address (as opposed to a private IP address). A
    public IP address exposes your laptop to attacks from the Internet at
    large, whether you are using WiFi, dialup, cable modem, DSL, or hotel
    business center (wired) Ethernet connections. If you were to monitor
    activity at hotspots using an Ethereal LAN analyzer, you would see
    attempts to connect to file shares on your system, as well as port scans
    and OS fingerprinting traffic coming into the wireless LAN from all over
    the Internet.

    Attacking Hotspots
    Public wireless networks heighten the risks of some exploits -- for
    example, eavesdropping is quite common at hotspots. An attacker doesn't
    need to be associated with a hotspot Access Point to monitor and capture
    traffic (it's radio!). By deploying a rogue AP, an attacker can perform
    numerous "man in the middle" attacks against a user. "Man in the middle"
    refers to a wide range of techniques where an attacker sits invisibly
    between two legitimate parties, intercepts their transmissions, and can
    passively spy, or actively modify the passing data without the legit
    parties realizing it. Classic "man in the middle" attacks include
    modifying data (changing "don't authorize" to "authorize"), injection
    (changing "pay $10.00" to "pay $10,000.00"), and replay (capturing
    passwords or authentication strings from a legitimate sign-on, then
    replaying them later to impersonate a valid user). Thus, rule number two
    for Hotspot users: use VPN to your workplace, and be certain to use SSL
    if you visit e-merchant, e-financial, or other sites where you may access
    and transmit sensitive or personal information. Attackers can still see
    your sessions, but since your data are encrypted, unless the attacker
    intends to target you specifically he will move on to the easier
    unencrypted victims.

    Denial of Hotspot Service
    My partner, Lisa Phifer, and I know of and have seen all sorts of denial
    of service attacks specifically designed for WLANs. For example, at the
    radio level, an attacker may try to jam a wireless network by injecting
    strong interfering radio signals at the network to overwhelm intended
    signals (but some countermeasures are possible, as described here). At
    the MAC level, attackers try to exploit the IEEE 802.11 medium
    arbitration algorithm (DCF) that is intended to prevent stations from
    transmitting at the same time. It's also possible to flood or airjack an
    access point with 802.11 Associate or Disassociate frames attacks, or
    attack an authentication system using a variety of IEEE 802.1x DoS
    attacks. Aruba Networks describes these and more DOS attacks here.

    Phishing for logins and credit cards
    One form of phishing specifically targets unsuspecting WiFi hotspot
    users. An attacker finds a location near a hotspot and operates a rogue
    AP (with a tool such as AirSNARF) to attract would-be customers of that
    hotspot. Anyone who associates with the rogue AP is directed to the
    attacker's Web site, which is designed to look like the sign-on or login
    portal of the hotspot operator. The duped user then submits access
    (account) credentials, personal and credit card information to the Web
    forms of the phony login. Attackers can sustain the attack beyond
    identity theft by eavesdropping traffic, or resolving DNS queries so that
    the user connects to the attacker's servers; for example, he might run
    bogus email servers in hopes of obtaining account information. Some
    organizations and ISPs support a single user account for mail, telnet,
    ftp and other intranet services. With a valid account and (quite
    possibly) server domain names in his pocket, the attacker can now attack
    the user's organization or an ISP.

    It is possible to monitor the Extended Service Set Identification
    (ESSID), AP and default gateway MAC addresses of a wireless network. You
    can watch for radical signal strength fluctuations to detect a rogue AP.
    But this kind of activity is way beyond the typical user. Thus, education
    is your best weapon: explain phishing to employees and family members,
    show them examples of phishing sites, and list ways they can distinguish
    phony sites from the real deals. If your company pays for your hotspot
    account, consider using a hotspot roaming service that automates secure
    end-to-end authentication so that you don't have to log into the
    hotspot's Web portal (e.g., iPass).

    Be prepared
    Don't be afraid to use hotspots, but do pay attention to security. If you
    are already protecting your laptop or handheld with antivirus and
    personal firewall software, and use a VPN or SSL for sessions where
    sensitive information is exchanged, you have effectively protected
    yourself against many threats and exploits. You can't do much about DoS
    attacks, so don't worry about them. But do have a back-up access plan if
    getting on-line is a business necessity. You can protect yourself against
    identity theft by studying the attack and, most of all, paying attention
    to what you're clicking on or responding to.

    Public wireless access is a wonderful tool, but you must use it wisely.
    Next time you sit in a hotspot with your wireless device, keep your guard
    up -- and let the wireless Hamburglars move on to the next victim. ##

    <snip>
  2. Archived from groups: alt.internet.wireless (More info?)

    billpritjr@spamhole.com (Bill) wrote:
    >I do have a firewall installed on my laptop

    What's a good firewall that I can load/unload on demand? When I'm on
    my home wired LAN, I want the firewall not just turned off, but
    completely gone.

    Thanks!

    --
    William Smith
    ComputerSmiths Consulting, Inc. www.compusmiths.com
  3. Archived from groups: alt.internet.wireless (More info?)

    Many hotspots do not allow the enabling of encryption while other do.
    If your hot spot is open, make sure you do not have file & print
    sharing enabled. Other than that, you appear to be taking the
    necessary steps to mprove security. As for email, I really don't have
    any suggestions. Sorry.

    On 19 Jun 2004 21:59:12 -0700, billpritjr@spamhole.com (Bill) wrote:

    >How can I improve my Wi-Fi security when surfing at free hot spots,
    >which exist at my local library and also on my local university
    >campus?
    >
    >I do have a firewall installed on my laptop and only use HTTPS sites
    >for credit card, bank, etc info. However my email is HTTP.
    >
    >any info is appreciated
    >
    >thanks
  4. Archived from groups: alt.internet.wireless (More info?)

    William wrote:
    > What's a good firewall that I can load/unload on demand? When I'm on
    > my home wired LAN, I want the firewall not just turned off, but
    > completely gone.

    I have ZoneLabs. ZoneAlarm is free. I have it configured so that my other
    home computers are "trusted". I don't disable it when I am at home, lest I
    forget to turn it back on when I go out in public.
    I also block most of the nonsense on the corporate network. There is a lot
    of virus probing and various other nonsense going on at work.
    http://www.zonelabs.com/store/content/company/products/znalm/freeDownload.jsp

    This one has an easy mode, and a learning mode. I chose the learning mode,
    which is annoying for the first few days as you get things set up, but I
    think it results in a fairly tight system.

    It does allow itself to be shutdown easily from the systray icon. It
    disappears and needs to be restarted from the program menu after that. I
    don't know if that's what you mean by "completely gone".

    --
    ---
    Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
  5. Archived from groups: alt.internet.wireless (More info?)

    dold@Wi-FiXsecu.usenet.us.com wrote:
    >William wrote:
    >> What's a good firewall that I can load/unload on demand? When I'm on
    >> my home wired LAN, I want the firewall not just turned off, but
    >> completely gone.
    >
    >I have ZoneLabs.

    I got the latest one, and it seems to do what I want (if I disallow
    it's automatic startup). Thanks! I had had all kinds of problems
    iwth ZA 2.1.44, but version 5 seems OK.

    Thanks again!

    --
    William Smith
    ComputerSmiths Consulting, Inc. www.compusmiths.com
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