Panic Attacks - Interpret Two Reports?

Question

Can someone read the EtreCheck report AND the Mac Mini generated report?  First EtreCheck, followed by the MacMini generated error report.
Thanks for looking thru this.
ETRECHECK REPORT.....
Problem description:
System reboots about once a day.  Recently upgraded to Yosemite, but issue didn’t start until about two weeks later.  MacMini, late 2009.
EtreCheck version: 2.0.11 (98)
Report generated November 15, 2014 at 4:14:09 PM EST
Hardware Information: ℹ️
  Mac mini (Early 2009) (Verified)
  Mac mini - model: Macmini3,1
  1 2.26 GHz Intel Core 2 Duo CPU: 2-core
  4 GB RAM Upgradeable
  BANK 0/DIMM0
  2 GB DDR3 1067 MHz ok
  BANK 1/DIMM0
  2 GB DDR3 1067 MHz ok
  Bluetooth: Old - Handoff/Airdrop2 not supported
  Wireless:  en1: 802.11 a/b/g/n
Video Information: ℹ️
  NVIDIA GeForce 9400 - VRAM: 256 MB
  HP L1950 1280 x 1024 @ 60 Hz
  HP L1950 1280 x 1024 @ 60 Hz
System Software: ℹ️
  OS X 10.10 (14A389) - Uptime: 1:36:57
Disk Information: ℹ️
  WDC WD3200BPVT-00JJ5T0 disk0 : (320.07 GB)
  S.M.A.R.T. Status: Verified
  EFI (disk0s1) <not mounted> : 210 MB
  Earth (disk0s2) /  [Startup]: 319.21 GB (286.10 GB free)
  Recovery HD (disk0s3) <not mounted>  [Recovery]: 650 MB
  PIONEER DVD-RW  DVRTS08
USB Information: ℹ️
  Iomega USB Zip 100
  Canon CanoScan
  Apple Computer, Inc. IR Receiver
  AKM AK5370
  Apple Inc. BRCM2046 Hub
  Apple Inc. Bluetooth USB Host Controller
Firewire Information: ℹ️
  Other World Computing OWC Neptune 400mbit - 400mbit max
  S.M.A.R.T. Status: Verified
  EFI (disk1s1) <not mounted> : 210 MB
  Time Machine (disk1s2) /Volumes/Time Machine : 79.68 GB (14.58 GB free)
Gatekeeper: ℹ️
  Mac App Store and identified developers
Kernel Extensions: ℹ️
  /Library/Extensions
  [loaded] com.symantec.kext.SymAPComm (12.7.1f4 - SDK 10.8) Support
  [loaded] com.symantec.kext.internetSecurity (5.4f4 - SDK 10.8) Support
  [loaded] com.symantec.kext.ips (3.9.2f1 - SDK 10.8) Support
Launch Agents: ℹ️
  [loaded] com.symantec.errorreporter-periodicagent.plist Support
  [running] com.symantec.uiagent.application.plist Support
Launch Daemons: ℹ️
  [loaded] com.adobe.fpsaud.plist Support
  [loaded] com.macpaw.CleanMyMac2.Agent.plist Support
  [loaded] com.microsoft.office.licensing.helper.plist Support
  [loaded] com.symantec.errorreporter-periodic.plist Support
  [loaded] com.symantec.liveupdate.daemon.ondemand.plist Support
  [loaded] com.symantec.liveupdate.daemon.plist Support
  [not loaded] com.symantec.nav.migrateqtf.plist Support
  [running] com.symantec.sharedsettings.plist Support
  [running] com.symantec.symdaemon.plist Support
User Launch Agents: ℹ️
  [loaded] com.adobe.ARM.[...].plist Support
  [loaded] com.macpaw.CleanMyMac2Helper.diskSpaceWatcher.plist Support
  [loaded] com.macpaw.CleanMyMac2Helper.scheduledScan.plist Support
  [loaded] com.macpaw.CleanMyMac2Helper.trashWatcher.plist Support
User Login Items: ℹ️
  iTunesHelper Application (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)
  AdobeResourceSynchronizer ApplicationHidden (/Applications/Adobe Reader.app/Contents/Support/AdobeResourceSynchronizer.app)
Internet Plug-ins: ℹ️
  FlashPlayer-10.6: Version: 15.0.0.223 - SDK 10.6 Support
  QuickTime Plugin: Version: 7.7.3
  AdobePDFViewerNPAPI: Version: 11.0.09 - SDK 10.6 Support
  AdobePDFViewer: Version: 11.0.09 - SDK 10.6 Support
  Flash Player: Version: 15.0.0.223 - SDK 10.6 Support
  Default Browser: Version: 600 - SDK 10.10
  SharePointBrowserPlugin: Version: 14.4.6 - SDK 10.6 Support
  Silverlight: Version: 5.1.30514.0 - SDK 10.6 Support
3rd Party Preference Panes: ℹ️
  Flash Player  Support
  Norton\nQuickMenu  Support
Time Machine: ℹ️
  Skip System Files: NO
  Mobile backups: OFF
  Auto backup: YES
  Volumes being backed up:
  Earth: Disk size: 319.21 GB Disk used: 33.11 GB
  Destinations:
  Time Machine [Local]
  Total size: 79.68 GB
  Total number of backups: 46
  Oldest backup: 2014-08-02 00:06:22 +0000
  Last backup: 2014-11-15 20:49:28 +0000
  Size of backup disk: Too small
  Backup size 79.68 GB < (Disk used 33.11 GB X 3)
Top Processes by CPU: ℹ️
      9% WindowServer
      4% Microsoft Word
      1% hidd
      1% loginwindow
      0% fontd
Top Processes by Memory: ℹ️
  309 MB SymDaemon
  108 MB Mail
  106 MB Microsoft Word
  92 MB WindowServer
  90 MB mds_stores
Virtual Memory Information: ℹ️
  546 MB Free RAM
  2.16 GB Active RAM
  594 MB Inactive RAM
  707 MB Wired RAM
  2.30 GB Page-ins
  2 MB Page-outs
The MAC MINI GENERATED REPORT
nonymous UUID: E52B4103-C016-0746-205E-B3E67A787267
Sat Nov 15 14:38:13 2014
*** Panic Report ***
panic(cpu 1 caller 0xffffff801b979458): "a freed zone element has been modified in zone kalloc.128: expected 0xdeadbeefdeadbeef but found 0xffffff8026d7d758, bits changed 0x2152416ff87a69b7, at offset 88 of 128 in element 0xffffff80267cf480, cookies 0x3f0011f95f151448 0x53521dac7f58969"@/SourceCache/xnu/xnu-2782.1.97/osfmk/kern/zalloc.c:496
Backtrace (CPU 1), Frame : Return Address
0xffffff80adf4a7c0 : 0xffffff801b93a811
0xffffff80adf4a840 : 0xffffff801b979458
0xffffff80adf4a970 : 0xffffff801be80585
0xffffff80adf4bab0 : 0xffffff801be81333
0xffffff80adf4bae0 : 0xffffff7f9cefa438
0xffffff80adf4bb20 : 0xffffff7f9cef9c5a
0xffffff80adf4bb60 : 0xffffff801bf026df
0xffffff80adf4bbc0 : 0xffffff801bf00003
0xffffff80adf4bd00 : 0xffffff801b9ea517
0xffffff80adf4be10 : 0xffffff801b93e91c
0xffffff80adf4be40 : 0xffffff801b9235a3
0xffffff80adf4be90 : 0xffffff801b933e8d
0xffffff80adf4bf10 : 0xffffff801ba0a142
0xffffff80adf4bfb0 : 0xffffff801ba3ac66
      Kernel Extensions in backtrace:
com.apple.iokit.IOSurface(97.0)[B4E2654D-4087-3875-9D59-E899A0A04F0E]@0xffffff7 f9cef3000->0xffffff7f9cf05fff
BSD process name corresponding to current thread: com.apple.WebKit
Mac OS version:
14A389
Kernel version:
Darwin Kernel Version 14.0.0: Fri Sep 19 00:26:44 PDT 2014; root:xnu-2782.1.97~2/RELEASE_X86_64
Kernel UUID: 89E10306-BC78-3A3B-955C-7C4922577E61
Kernel slide: 0x000000001b600000
Kernel text base: 0xffffff801b800000
__HIB  text base: 0xffffff801b700000
System model name: Macmini3,1 (Mac-F22C86C8)
System uptime in nanoseconds: 34279379927671
last loaded kext at 29156503458258: com.apple.driver.AppleUSBCDC      4.2.2b5 (addr 0xffffff7f9de68000, size 20480)
last unloaded kext at 30182695045545: com.apple.driver.AppleUSBCDC  4.2.2b5 (addr 0xffffff7f9de68000, size 16384)
loaded kexts:
com.symantec.kext.SymAPComm     12.7.1f4
com.symantec.kext.ips           3.9.2f1
com.symantec.kext.internetSecurity   5.4f4
com.apple.driver.AppleHWSensor    1.9.5d0
com.apple.driver.ApplePlatformEnabler        2.1.0d1
com.apple.driver.AGPM        100.14.37
com.apple.filesystems.autofs 3.0
com.apple.driver.AppleBluetoothMultitouch           85.3
com.apple.iokit.IOBluetoothSerialManager   4.3.0f10
com.apple.driver.AppleOSXWatchdog          1
com.apple.driver.AppleHDA 266.5
com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport 4.3.0f10
com.apple.driver.AudioAUUC          1.70
com.apple.iokit.IOUserEthernet        1.0.1
com.apple.Dont_Steal_Mac_OS_X   7.0.0
com.apple.driver.AppleHWAccess    1
com.apple.driver.AppleHV    1
com.apple.driver.ACPI_SMC_PlatformPlugin          1.0.0
com.apple.GeForceTesla        10.0.0
com.apple.driver.AppleLPC  1.7.3
com.apple.driver.AppleUpstreamUserClient            3.6.1
com.apple.driver.AppleMCCSControl          1.2.10
com.apple.driver.AppleIRController 327.5
com.apple.driver.Oxford_Semi           3.5.0
com.apple.AppleFSCompression.AppleFSCompressionTypeDataless       1.0.0d1
com.apple.AppleFSCompression.AppleFSCompressionTypeZlib  1.0.0d1
com.apple.BootCache 35
com.apple.iokit.SCSITaskUserClient 3.7.0
com.apple.driver.XsanFilter   404
com.apple.iokit.IOAHCIBlockStorage           2.6.5
com.apple.driver.AppleUSBHub       705.4.1
com.apple.driver.AppleUSBOHCI    656.4.1
com.apple.driver.AppleUSBEHCI     705.4.14
com.apple.driver.AirPortBrcm43224 700.36.24
com.apple.driver.AppleFWOHCI      5.5.2
com.apple.driver.AppleAHCIPort     3.0.7
com.apple.driver.AppleHPET           1.8
com.apple.nvenet        2.0.22
com.apple.driver.AppleRTC  2.0
com.apple.driver.AppleACPIButtons           3.1
com.apple.driver.AppleSMBIOS       2.1
com.apple.driver.AppleACPIEC       3.1
com.apple.driver.AppleAPIC            1.7
com.apple.driver.AppleIntelCPUPowerManagementClient  218.0.0
com.apple.nke.applicationfirewall      161
com.apple.security.quarantine            3
com.apple.security.TMSafetyNet     8
com.apple.driver.AppleIntelCPUPowerManagement           218.0.0
com.apple.AppleGraphicsDeviceControl      3.7.21
com.apple.kext.triggers           1.0
com.apple.driver.IOBluetoothHIDDriver      4.3.0f10
com.apple.driver.AppleMultitouchDriver     260.30
com.apple.iokit.IOSerialFamily          11
com.apple.driver.DspFuncLib            266.5
com.apple.kext.OSvKernDSPLib       1.15
com.apple.iokit.IOBluetoothHostControllerUSBTransport 4.3.0f10
com.apple.iokit.IOSurface      97
com.apple.iokit.IOBluetoothFamily  4.3.0f10
com.apple.driver.AppleSMC 3.1.9
com.apple.driver.IOPlatformPluginLegacy    1.0.0
com.apple.nvidia.classic.NVDANV50HalTesla         10.0.0
com.apple.iokit.IOUSBUserClient     705.4.0
com.apple.iokit.IOFireWireIP            2.2.6
com.apple.driver.AppleHDAController        266.5
com.apple.iokit.IOHDAFamily         266.5
com.apple.driver.IOPlatformPluginFamily    5.8.0d49
com.apple.driver.AppleSMBusController     1.0.13d1
com.apple.nvidia.classic.NVDAResmanTesla           10.0.0
com.apple.iokit.IONDRVSupport     2.4.1
com.apple.iokit.IOGraphicsFamily    2.4.1
com.apple.driver.AppleUSBAudio    295.22
com.apple.iokit.IOAudioFamily        200.6
com.apple.vecLib.kext            1.2.0
com.apple.iokit.IOSCSIBlockCommandsDevice       3.7.0
com.apple.iokit.IOUSBHIDDriver    705.4.0
com.apple.iokit.IOUSBMassStorageClass     3.7.0
com.apple.driver.AppleUSBMergeNub         705.4.0
com.apple.driver.AppleUSBComposite        705.4.9
com.apple.iokit.IOSCSIReducedBlockCommandsDevice      3.7.0
com.apple.iokit.IOFireWireSerialBusProtocolTransport       2.5.1
com.apple.iokit.IOFireWireSBP2       4.2.5
com.apple.iokit.IOSCSIMultimediaCommandsDevice          3.7.0
com.apple.iokit.IOBDStorageFamily 1.7
com.apple.iokit.IODVDStorageFamily          1.7.1
com.apple.iokit.IOCDStorageFamily 1.7.1
com.apple.iokit.IOAHCISerialATAPI           2.6.1
com.apple.iokit.IOSCSIArchitectureModelFamily    3.7.0
com.apple.iokit.IOUSBFamily           705.4.14
com.apple.iokit.IO80211Family        700.52
com.apple.iokit.IOFireWireFamily    4.5.6
com.apple.driver.AppleEFINVRAM            2.0
com.apple.iokit.IOAHCIFamily        2.7.0
com.apple.driver.AppleEFIRuntime  2.0
com.apple.iokit.IONetworkingFamily           3.2
com.apple.driver.NVSMU     2.2.9
com.apple.iokit.IOHIDFamily           2.0.0
com.apple.iokit.IOSMBusFamily      1.1
com.apple.security.sandbox   300.0
com.apple.kext.AppleMatch  1.0.0d1
com.apple.driver.AppleKeyStore      2
com.apple.driver.AppleMobileFileIntegrity  1.0.5
com.apple.driver.AppleCredentialManager   1.0
com.apple.driver.DiskImages 389.1
com.apple.iokit.IOStorageFamily       2.0
com.apple.iokit.IOReportFamily       31
com.apple.driver.AppleFDEKeyStore           28.30
com.apple.driver.AppleACPIPlatform          3.1
com.apple.iokit.IOPCIFamily            2.9
com.apple.iokit.IOACPIFamily         1.4
com.apple.kec.corecrypto      1.0
com.apple.kec.Libm    1
com.apple.kec.pthread            1
Model: Macmini3,1, BootROM MM31.0081.B06, 2 processors, Intel Core 2 Duo, 2.26 GHz, 4 GB, SMC 1.35f0
Graphics: NVIDIA GeForce 9400, NVIDIA GeForce 9400, PCI, 256 MB
Memory Module: BANK 0/DIMM0, 2 GB, DDR3, 1067 MHz, 0x80AD, 0x484D54313235533641465238432D47372020
Memory Module: BANK 1/DIMM0, 2 GB, DDR3, 1067 MHz, 0x80AD, 0x484D54313235533641465238432D47372020
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x90), Broadcom BCM43xx 1.0 (5.10.131.36.16)
Bluetooth: Version 4.3.0f10 14890, 3 services, 27 devices, 1 incoming serial ports
Network Service: Ethernet, Ethernet, en0
Serial ATA Device: WDC WD3200BPVT-00JJ5T0, 320.07 GB
Serial ATA Device: PIONEER DVD-RW  DVRTS08
USB Device: USB 2.0 Hub
USB Device: USB Zip 100
USB Device: CanoScan
USB Device: IR Receiver
USB Device: AK5370
USB Device: BRCM2046 Hub
USB Device: Bluetooth USB Host Controller
FireWire Device: OWC Neptune, Other World Computing, Up to 400 Mb/sec
Thunderbolt Bus:

Answer 1

Mac users often ask whether they should install "anti-virus" software. The answer usually given on ASC is "no." The answer is right, but it may give the wrong impression that there is no threat from what are loosely called "viruses." There  is a threat, and you need to educate yourself about it.
1. This is a comment on what you should—and should not—do to protect yourself from malicious software ("malware") that circulates on the Internet and gets onto a computer as an unintended consequence of the user's actions. It does not apply to software, such as keystroke loggers, that may be installed deliberately by an intruder who has hands-on access to the computer, or who has been able to take control of it remotely. That threat is in a different category, and there's no easy way to defend against it.
The comment is long because the issue is complex. The key points are in sections 5, 6, and 10.
OS X now implements three layers of built-in protection specifically against malware, not counting runtime protections such as execute disable, sandboxing, system library randomization, and address space layout randomization that may also guard against other kinds of exploits.
2. All versions of OS X since 10.6.7 have been able to detect known Mac malware in downloaded files, and to block insecure web plugins. This feature is transparent to the user. Internally Apple calls it "XProtect."
The malware recognition database used by XProtect is automatically updated; however, you shouldn't rely on it, because the attackers are always at least a day ahead of the defenders.
The following caveats apply to XProtect:
☞ It can be bypassed by some third-party networking software, such as BitTorrent clients and Java applets.
☞ It only applies to software downloaded from the network. Software installed from a CD or other media is not checked.
As new versions of OS X are released, it's not clear whether Apple will indefinitely continue to maintain the XProtect database of older versions such as 10.6. The security of obsolete system versions may eventually be degraded. Security updates to the code of obsolete systems will stop being released at some point, and that may leave them open to other kinds of attack besides malware.
3. Starting with OS X 10.7.5, there has been a second layer of built-in malware protection, designated "Gatekeeper" by Apple. By default, applications and Installer packages downloaded from the network will only run if they're digitally signed by a developer with a certificate issued by Apple. Software certified in this way hasn't necessarily been tested by Apple, but you can be reasonably sure that it hasn't been modified by anyone other than the developer. His identity is known to Apple, so he could be held legally responsible if he distributed malware. That may not mean much if the developer lives in a country with a weak legal system (see below.)
Gatekeeper doesn't depend on a database of known malware. It has, however, the same limitations as XProtect, and in addition the following:
☞ It can easily be disabled or overridden by the user.
☞ A malware attacker could get control of a code-signing certificate under false pretenses, or could simply ignore the consequences of distributing codesigned malware.
☞ An App Store developer could find a way to bypass Apple's oversight, or the oversight could fail due to human error.
Apple has so far failed to revoke the codesigning certificates of some known abusers, thereby diluting the value of Gatekeeper and the Developer ID program. These failures don't involve App Store products, however.
For the reasons given, App Store products, and—to a lesser extent—other applications recognized by Gatekeeper as signed, are safer than others, but they can't be considered absolutely safe. "Sandboxed" applications may prompt for access to private data, such as your contacts, or for access to the network. Think before granting that access. Sandbox security is based on user input. Never click through any request for authorization without thinking.
4. Starting with OS X 10.8.3, a third layer of protection has been added: a "Malware Removal Tool" (MRT). MRT runs automatically in the background when you update the OS. It checks for, and removes, malware that may have evaded the other protections via a Java exploit (see below.) MRT also runs when you install or update the Apple-supplied Java runtime (but not the Oracle runtime.) Like XProtect, MRT is effective against known threats, but not against unknown ones. It notifies you if it finds malware, but otherwise there's no user interface to MRT.
5. The built-in security features of OS X reduce the risk of malware attack, but they are not, and never will be, complete protection. Malware is foremost a problem of human behavior, and no technological fix alone is going to solve it. Trusting software to protect you will only make you more vulnerable.
The best defense is always going to be your own intelligence. With the possible exception of Java exploits, all known malware circulating on the Internet that affects a fully-updated installation of OS X 10.6 or later takes the form of so-called "Trojan horses," which can only have an effect if the victim is duped into running them. The threat therefore amounts to a battle of wits between you and Internet criminals. If you're better informed than they think you are, you'll win. That means, in practice, that you always stay within a safe harbor of computing practices. How do you know when you're leaving the safe harbor? Below are some warning signs of danger.
Software from an untrustworthy source
☞ Software with a corporate brand, such as Adobe Flash Player, doesn't come directly from the developer’s website. Do not trust an alert from any website to update Flash, or your browser, or any other software. A genuine alert that Flash is outdated and blocked is shown on this support page. Follow the instructions on the support page in that case. Otherwise, assume that the alert is fake and someone is trying to scam you into installing malware. If you see such alerts on more than one website, ask for instructions.
☞ Software of any kind is distributed via BitTorrent, or Usenet, or on a website that also distributes pirated music or movies.
☞ Rogue websites such as Softonic, Soft32, and CNET Download distribute free applications that have been packaged in a superfluous "installer."
☞ The software is advertised by means of spam or intrusive web ads. Any ad, on any site, that includes a direct link to a download should be ignored.
Software that is plainly illegal or does something illegal
☞ High-priced commercial software such as Photoshop is "cracked" or "free."
☞ An application helps you to infringe copyright, for instance by circumventing the copy protection on commercial software, or saving streamed media for reuse without permission. All "YouTube downloaders" are in this category, though not all are necessarily malicious.
Conditional or unsolicited offers from strangers
☞ A telephone caller or a web page tells you that you have a “virus” and offers to help you remove it. (Some reputable websites did legitimately warn visitors who were infected with the "DNSChanger" malware. That exception to this rule no longer applies.)
☞ A web site offers free content such as video or music, but to use it you must install a “codec,” “plug-in,” "player," "downloader," "extractor," or “certificate” that comes from that same site, or an unknown one.
☞ You win a prize in a contest you never entered.
☞ Someone on a message board such as this one is eager to help you, but only if you download an application of his choosing.
☞ A "FREE WI-FI !!!" network advertises itself in a public place such as an airport, but is not provided by the management.
☞ Anything online that you would expect to pay for is "free."
Unexpected events
☞ A file is downloaded automatically when you visit a web page, with no other action on your part. Delete any such file without opening it.
☞ You open what you think is a document and get an alert that it's "an application downloaded from the Internet." Click Cancel and delete the file. Even if you don't get the alert, you should still delete any file that isn't what you expected it to be.
☞ An application does something you don't expect, such as asking for permission to access your contacts, your location, or the Internet for no obvious reason.
☞ Software is attached to email that you didn't request, even if it comes (or seems to come) from someone you trust.
I don't say that leaving the safe harbor just once will necessarily result in disaster, but making a habit of it will weaken your defenses against malware attack. Any of the above scenarios should, at the very least, make you uncomfortable.
6. Java on the Web (not to be confused with JavaScript, to which it's not related, despite the similarity of the names) is a weak point in the security of any system. Java is, among other things, a platform for running complex applications in a web page, on the client. That was always a bad idea, and Java's developers have proven themselves incapable of implementing it without also creating a portal for malware to enter. Past Java exploits are the closest thing there has ever been to a Windows-style virus affecting OS X. Merely loading a page with malicious Java content could be harmful.
Fortunately, client-side Java on the Web is obsolete and mostly extinct. Only a few outmoded sites still use it. Try to hasten the process of extinction by avoiding those sites, if you have a choice. Forget about playing games or other non-essential uses of Java.
Java is not included in OS X 10.7 and later. Discrete Java installers are distributed by Apple and by Oracle (the developer of Java.) Don't use either one unless you need it. Most people don't. If Java is installed, disable it—not JavaScript—in your browsers.
Regardless of version, experience has shown that Java on the Web can't be trusted. If you must use a Java applet for a task on a specific site, enable Java only for that site in Safari. Never enable Java for a public website that carries third-party advertising. Use it only on well-known, login-protected, secure websites without ads. In Safari 6 or later, you'll see a padlock icon in the address bar when visiting a secure site.
Stay within the safe harbor, and you’ll be as safe from malware as you can practically be. The rest of this comment concerns what you should not do to protect yourself.
7. Never install any commercial "anti-virus" (AV) or "Internet security" products for the Mac, as they are all worse than useless. If you need to be able to detect Windows malware in your files, use one of the free security apps in the Mac App Store—nothing else.
Why shouldn't you use commercial AV products?
☞ To recognize malware, the software depends on a database of known threats, which is always at least a day out of date. This technique is a proven failure, as a major AV software vendor has admitted. Most attacks are "zero-day"—that is, previously unknown. Recognition-based AV does not defend against such attacks, and the enterprise IT industry is coming to the realization that traditional AV software is worthless.
☞ Its design is predicated on the nonexistent threat that malware may be injected at any time, anywhere in the file system. Malware is downloaded from the network; it doesn't materialize from nowhere. In order to meet that nonexistent threat, commercial AV software modifies or duplicates low-level functions of the operating system, which is a waste of resources and a common cause of instability, bugs, and poor performance.
☞ By modifying the operating system, the software may also create weaknesses that could be exploited by malware attackers.
☞ Most importantly, a false sense of security is dangerous.
8. An AV product from the App Store, such as "ClamXav," has the same drawback as the commercial suites of being always out of date, but it does not inject low-level code into the operating system. That doesn't mean it's entirely harmless. It may report email messages that have "phishing" links in the body, or Windows malware in attachments, as infected files, and offer to delete or move them. Doing so will corrupt the Mail database. The messages should be deleted from within the Mail application.
An AV app is not needed, and cannot be relied upon, for protection against OS X malware. It's useful, if at all, only for detecting Windows malware, and even for that use it's not really effective, because new Windows malware is emerging much faster than OS X malware.
Windows malware can't harm you directly (unless, of course, you use Windows.) Just don't pass it on to anyone else. A malicious attachment in email is usually easy to recognize by the name alone. An actual example:
London Terror Moovie.avi [124 spaces] Checked By Norton Antivirus.exe
You don't need software to tell you that's a Windows trojan. Software may be able to tell you which trojan it is, but who cares? In practice, there's no reason to use recognition software unless an organizational policy requires it. Windows malware is so widespread that you should assume it's in every email attachment until proven otherwise. Nevertheless, ClamXav or a similar product from the App Store may serve a purpose if it satisfies an ill-informed network administrator who says you must run some kind of AV application. It's free and it won't handicap the system.
The ClamXav developer won't try to "upsell" you to a paid version of the product. Other developers may do that. Don't be upsold. For one thing, you should not pay to protect Windows users from the consequences of their choice of computing platform. For another, a paid upgrade from a free app will probably have all the disadvantages mentioned in section 7.
9. It seems to be a common belief that the built-in Application Firewall acts as a barrier to infection, or prevents malware from functioning. It does neither. It blocks inbound connections to certain network services you're running, such as file sharing. It's disabled by default and you should leave it that way if you're behind a router on a private home or office network. Activate it only when you're on an untrusted network, for instance a public Wi-Fi hotspot, where you don't want to provide services. Disable any services you don't use in the Sharing preference pane. All are disabled by default.
10. As a Mac user, you don't have to live in fear that your computer may be infected every time you install software, read email, or visit a web page. But neither can you assume that you will always be safe from exploitation, no matter what you do. Navigating the Internet is like walking the streets of a big city. It's as safe or as dangerous as you choose to make it. The greatest harm done by security software is precisely its selling point: it makes people feel safe. They may then feel safe enough to take risks from which the software doesn't protect them. Nothing can lessen the need for safe computing practices.