Avoid malware infections spread via "QUOTE YOUR BEST PRICE" spam email

What is the "QUOTE YOUR BEST PRICE" email?

After inspecting the "QUOTE YOUR BEST PRICE" email, our researchers determined that it is malspam. Scam emails designed to distribute malware are sent through mass-scale spam campaigns (malspam).

The email in question is yet another example of the purchase/product scam model, whereby recipients are tricked into opening a malicious attachment disguised as a product order.

"QUOTE YOUR BEST PRICE" email virus overview

The "QUOTE YOUR BEST PRICE" spam email makes the request evident in this name (to make the best offer for a product). It also asks the recipients to review the provided delivery times. The letter then lists fake sender/contact details, and it is concluded with a confidentiality notice.

It must be stressed that the information given by this email - is false. Therefore, when the file attached to this email is opened - malware download/installation is jumpstarted.

We have researched thousands of spam emails and have observed them being used to spread all manner of malicious programs. To elaborate on how some of them operate, ransomware is designed to encrypt files and/or lock the device's screen - to demand ransoms for the decryption/ access recovery.

Cryptocurrency miners generate cryptocurrency by abusing system resources, potentially to the point of rendering the system unresponsive or causing it to fail.

"Trojan" is a term encompassing a wide range of malicious software. These programs can be capable of establishing remote control over infected machines (RATs - Remote Access Trojans), downloading files and data, extracting information from browsers and other apps, causing chain infections, spying (e.g., recording keystrokes [keyloggers], audio/video via microphones and cameras, etc.), replacing clipboard (copy-paste buffer) data, and so on.

The threats posed by a malicious program depend on its abilities and the cyber criminals' goals. Generally, malware infections can result in decreased system performance or failure, permanent data loss, hardware damage, severe privacy issues, financial losses, and identity theft. These dangers are also posed by the "QUOTE YOUR BEST PRICE" email. If your system has been infected, we strongly advise using an anti-virus to remove the threats without delay.

Malspam campaign examples

"We Receive Another Bank Information", "AIC Contracting", and "FITS email virus" are just a few examples of the malware-spreading emails we have analyzed. Spam mail is usually presented as "important", "urgent", or similar; it may also be disguised as messages from genuine authorities, institutions, companies, service providers, etc.

Agent Tesla, Emotet, TrickBot - are a couple examples of malware commonly proliferated via these letters. In addition to malicious program distribution, spam emails are used for phishing and other scams.

How do spam campaigns infect computers?

Spam emails can contain infectious files as attachments or download links. The files can be archives, executables, Microsoft Office and PDF documents, JavaScript, etc. Once a malicious file is executed, run, or otherwise opened - malware download/installation is initiated.

For example, Microsoft Office documents infect systems by executing malicious macro commands. This process is immediate in Microsoft Office versions released before 2010.

Later versions have "Protected View" mode that prevents macro execution upon a document's opening. Instead, users have to manually enable macro commands (i.e., editing/content); note that virulent documents often contain deceptive messages designed to trick users into allowing macros.

How to avoid installation of malware?

We advise against opening/clicking the attachments and links found in suspicious/irrelevant emails, since they can contain malware. Another recommendation is using Microsoft Office versions released after 2010.

However, malicious software is not proliferated exclusively via spam mail. Therefore, download only from official and verified channels. Furthermore, activate and update programs with tools provided by legitimate developers, as those obtained from third-parties may cause system infections.

We must emphasize the importance of having a reputable anti-virus installed and updated. Security software must be used to run regular system scans and to remove detected threats/issues. If you've already opened malicious attachments, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

Text presented in the "QUOTE YOUR BEST PRICE" email letter:

Subject: Re:RFQ# QMBT-2215-214

DEAR SIR

PLEASE QUOTE YOUR BEST PRICE & CHECK THE DELIVERY LEAD TIME :

QTY : 2 SET

QTY : 1 SET

THANKS AND REGARDS

 

Parth Sir

Executive Officer

2nd Floor, Cheran Plaza

1090, Trichy Road, Coimbatore – 641 018

Ph : 0422-2304775/6/9

________________________________
This email and any attachments are confidential and intended
solely for the addressee. If you are not the intended recipient,
any disclosure, copying, distribution either whole or partial,
is prohibited and may be unlawful. In such case, please delete this message and
kindly notify the sender. Kuala Lumpur Kepong Berhad
________________________________

Screenshot of VirusTotal detections of the malicious attachment distributed via "QUOTE YOUR BEST PRICE" spam campaign ("New Order# 06012595-021422.rev"):

Another example of an email from this spam campaign spreading malware:

Text presented within:

Subject: Urgent Request-HUTH.INTERNATIONAL.COM

 

Ladies and gentlemen,

I will appreciate your best price and delivery time on the following equipment and spares as attached.

NOTE: WITH YOUR QUOTE SEND THE DRAWING AND DATASHEET.

Deadline:14.11.2022.

I look forward your kind reply

Best regards,

Natalya Pidchenko
Marketing and Sales Administration

HUTH.INTERNATIONAL.COM e.K

International Trading Company

Birkenhainerstrasse 2

D-63579 Free Court

Phone: +49(0) 6055 90 61 049

Fax:  +49(0) 6055 93 54 65

Internet: www.huth-international.com

E-Mail: natalja.pidtchenko@huth-international.com

Ust./VA-Ident-No.: DE813711822

District Court Hanau: HRA 92627

Another example of price quotation-themed spam email spreading FormBook malware:

Text presented within:

Subject: TOP URGENT RFQ (KSA)

 

Hello Sir/Madam,

My name is Ahmed Mostafa, I represent my company (Systematic Construction Ltd.) We are looking to purcahse some materials for our new project in Saudi Arabia.
Our business partner from China gave us your contact details.

I will be glad if you can help us with an urgent quote based on our RFQ attached.

Kindly let us know your mode of payment and terms of delivery.

I look forward to your quotation.

Kind regards,

Amed Mostafa
Address​

18 A, Obour Buildings,Salah Salem 18th , Apartment 8

02-26833592

Yet another example of a malware-spreading email from "QUOTE YOUR BEST PRICE" spam campaign:

Text presented within:

Subject: Product inquiry

Hi,

I hope you are doing well. please provide me your most recent price as well as a copy of your catalog if available. We would like to place an order as soon as possible. View the order specification on the attached file.

Download File
-
Please let us know your best, competitive quotes as well as FOB and EXW rates.

Thank you for your early comments.

 

Regards

Name: Patricia Bruce
Position: Purchase Manager
Company: PEDDLE GROUPS SL
Address: Carrer Conradors, 11A, 07141 Poligono
Industrialde Marratxi, Illes Balears, Spain
Email: info@peddle-group.com, patricia@holimann.com

Yet another example of an email from "QUOTE YOUR BEST PRICE" spam campaign:

Text presented within:

Subject: RFQ- SEA/AIR FREIGHT-VARIOUS ITEMS

 

Good day,

Kindly quote us your best price and delivery for the attached below

SALES QUOTE

Best Regards

Tian Jin
Procurement Specialist
Multinational Trade Co., LTD

Head Office: 1018 Wanda Centre, Anyang, Henan, China

GNEE PTE. LTD.

8 KAKI BUKIT AVENUE 4 #03-21 PREMIER @KAKI BUKIT SINGAPORE(415875)

GNEE CO., LIMITED

SUITE 913B 9/F OCEAN CTR HARBOUR CITY 5 CANTON RD TST KLN HONG KONG

Tel: +86 373 5055135 Fax: +86 362 5055180

Screenshot of the phishing site promoted using this email:

Yet another example of an email from "QUOTE YOUR BEST PRICE" spam campaign:

Text presented within:

Subject: Purchase Order FPO-11/2024 against ER/PUR/IE-05/2023 for the supply of 1111 A/B

 

Good Day -,

Kindly refer to the attached our new purchase order 4902134 and provide us Quotation of your best prices.

ALSO, Kindly share statement of accounts as of 29.31.23 to do reconcile, and process payment.

Note: Statement received on or before 25.01.24 will be consider in the payment schedule or vice versa.

Do not include "Jan 08" invoices if any

Please Ignore this email if you have already shared SOA.

Thanks in advance.

Jeremy FUENTES

NDT Sales Manager Frnce, Belgium, Spain, Portugal
Email:     jeremy.fuentes@carestream .com
Mobile: +33 (0)6 07 73 82 3

Screenshot of the attached HTML phishing document:

Yet another example of an email from "QUOTE YOUR BEST PRICE" spam campaign:

Text presented within:

Subject: PO-4103586287

 

Hello Team,

I would like to place an order for potential items in our range, would you please check the attached for your reference and quote your best  prices and Delivery/Lead time accordingly.

Awaiting your early feedback.

Thank You,
Ajit Kulkarni
MeRCK

Sigma-Aldrich|7th Floor, eCity Tower2, Electronic City Phase1| Bangalore | India
Email: ajit.kulkarni@merckgroup.com

Screenshot of the attached malicious HTML document used for phishing purposes:

Instant automatic malware removal:

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Types of malicious emails:

If you opened an attachment or downloaded a file from a suspicious email, run a full system scan with Combo Cleaner. If you only received the email and didn't engage with it, you don't need to scan anything - just identify the scam and delete it. The full procedure below covers both situations and what to do if you already clicked, replied, or sent money.

Credential theft Phishing emails

Fake login pages disguised as PayPal, Microsoft, Apple, banks, or social networks. The email pushes a link to a near-perfect copy of the real login screen. The moment you type your username and password, the attacker has them.

Common subject lines

• "Action required: confirm your account"
• "Your password expires today"
• "Unusual sign-in attempt detected"
• "Verify your billing information"

Malware delivery Emails with malicious attachments

Trojans hidden inside fake invoices, faxes, shipping confirmations, or Office documents. Opening the attachment runs the payload and infects the system - often with an info-stealer or remote-access trojan.

Common subject lines

• "Invoice INV-2026-XXXX attached"
• "Fax received - 3 pages"
• "Your shipping document is ready"
• "Voicemail from +1-XXX-XXX-XXXX"

Extortion Sextortion emails

Fake claims of webcam recordings demanding cryptocurrency. Almost always a bluff: the attacker pulls a real password from an old data breach to make the threat look credible, then claims to have video of you. They have no recording and no access.

Common subject lines

• "I know your password is XXXX"
• "Your account has been hacked"
• "I have recorded you - 48 hours to pay"
• "You have been compromised"

Callback fraud Refund & callback scams

"Your subscription was renewed for $499 - call to cancel." Norton, McAfee, Geek Squad, PayPal, and Wells Fargo variants are all common. There's no real subscription. The phone number in the email connects directly to the scammer, who walks you through "refunding" yourself - which is actually them stealing money from your bank.

Common subject lines

• "Norton subscription auto-renewed - $499.99"
• "McAfee Total Protection invoice"
• "Geek Squad order confirmation"
• "Your PayPal payment is being processed"

Credential theft Account suspension & verification scams

"Your account will be deleted in 24 hours - verify now." The artificial deadline is the whole point: it pressures you to click before checking details. The "verify" link goes to a phishing page styled to look like the real provider.

Common subject lines

• "Your account will be deleted in 24 hours"
• "Suspicious activity detected - verify now"
• "Final warning: account closure"
• "Action required to keep your account active"

Mixed payload Delivery & package scams

Fake DHL, USPS, UPS, or FedEx tracking, customs fees, or "package undeliverable" notices. Targets anyone expecting a parcel - the timing alone catches many people. The link hides either phishing (asking for card details to "release" the package) or a malware download.

Common subject lines

• "Your DHL package is held at customs"
• "USPS - delivery attempt failed"
• "FedEx tracking update - action required"
• "Pay $2.99 redelivery fee to release your parcel"

Remote access Tech support scams

Fake Microsoft, Apple, or "Windows Defender" security alerts pushing a phone number. Real Microsoft and Apple never email a phone number to call. The number connects you to a scammer who asks for remote access to "fix" the imaginary problem and then demands payment.

Common subject lines

• "Microsoft Defender expired - renew now"
• "Apple ID security alert"
• "Critical: virus detected on your PC"
• "Windows license expired - call now"

Wire fraud Advance-fee scams

Inheritance, lottery wins, romance, or business deals that ask for a small fee to release a much larger sum. The classic "Nigerian prince" 419 family of frauds. Once you pay the first fee, more fees appear (taxes, lawyer, transfer charges) until you stop paying. The promised money never exists.

Common subject lines

• "Inheritance from a relative you didn't know about"
• "You won the international lottery"
• "URGENT - business proposal worth $XX million"
• "Compensation fund release for fraud victims"

Wire fraud Business email compromise (BEC)

CEO impersonation asking employees to wire money or buy gift cards, or fake supplier invoices with newly "updated" bank details for payment redirection. The email often spoofs a real internal executive's display name and uses an external lookalike domain.

Common subject lines

• "Quick task - need you to buy gift cards"
• "Updated banking details for invoice payment"
• "Wire transfer request - urgent"
• "Are you available?" (CEO impersonation opener)

How to spot a malicious email?

Phase 1~ 2 min

Spot - identify the red flags

---

1

Check the sender's actual address, not the display name

30 sec

The display name (the human-readable part) is trivial to fake. Always check the full address that comes after it. Common red flags:

• Domain mismatch - service@paypa1.com, support@micros0ft-help.com, look-alike domains using digits or extra hyphens
• Free-email impersonation - any "official" message from a bank, courier, or platform sent from a @gmail.com, @outlook.com, or @yahoo.com address
• Reply-To mismatch - the From address looks legitimate but Reply-To points somewhere completely different

Why this matters

Real companies own their domains and send mail from them. A "DHL" message from a Gmail address is never legitimate, regardless of how convincing the body looks.

2

Watch for urgency, threats, and generic greetings

30 sec

Scams almost always rush you. The point is to make you act before you think. Treat any of the following as a strong signal:

• "Your account will be deleted in 24 hours"
• "Final notice" / "Immediate action required"
• "Dear Customer" or "Dear User" instead of your real name
• Threats of fines, account closure, legal action, or arrest
• Promises of refunds, prizes, or money you didn't earn
• Spelling and grammar mistakes in messages claiming to come from a major brand

3

Hover over every link before clicking

30 sec

On a desktop, hover the mouse over the link without clicking. The real destination shows in the bottom-left status bar of your browser or email client. On a phone, long-press the link to preview the URL.

• Real Microsoft, PayPal, or bank links go to those exact domains, not redirects through unrelated sites
• Shortened URLs (bit.ly, tinyurl, t.co) hide the real destination - never click them in unsolicited mail
• The visible link text and the actual URL must match - mismatches are the single biggest phishing red flag

Pro tip

When in doubt, don't click the link. Open a new browser tab and type the company's address yourself, then log in normally. If there really is an issue with your account, you'll see it there.

4

Treat unexpected attachments as hostile

30 sec

If you didn't ask for the file, don't open it - even if it appears to come from someone you know. Categories that should never be opened from email without verification through another channel:

• .exe, .scr, .iso, .img, .vbs, .bat - executables, never legitimate attachments
• .docx, .xlsx, .pptx with "Enable macros" prompts - the macros run the malware
• .pdf with "Click here to view" buttons - usually a phishing redirect, not a real document
• .zip, .rar, .7z archives, especially password-protected ones - the password defeats the email scanner

Phase 2~ 2 min

Report and delete - if you haven't engaged

---

If you only received the email and didn't reply, click, or open anything, the steps below are all you need. Your computer is not infected.

5

Don't reply, don't click "unsubscribe"

30 sec

Replying confirms your address is real and monitored, which gets you added to higher-value scam lists. The "unsubscribe" link in a scam message is rarely a real opt-out - it usually leads to a phishing page or downloads a tracking pixel.

Instead, mark the message as junk or phishing inside your email client (this trains the spam filter), then block the sender.

6

Report the scam to your email provider and authorities

1 min

Inside your email client:

• Gmail: open the message → ⋮ menu → Report phishing
• Outlook / Outlook.com: ⋯ menu → Report → Report phishing
• Apple Mail / iCloud: Move to Junk, then forward to reportphishing@apple.com

Forward or report to authorities:

• International: forward to reportphishing@apwg.org
• United States: ic3.gov (FBI)
• United Kingdom: forward phishing emails to report@phishing.gov.uk (NCSC SERS); for financial loss report at reportfraud.police.uk (Report Fraud, the successor to Action Fraud; 0300 123 2040)
• Canada: antifraudcentre.ca
• Australia: scamwatch.gov.au
• EU: your national CERT - find yours via the ENISA CSIRT map

After reporting, delete the email and empty the Trash folder so you don't accidentally open it later.

Phase 3~ 10–60 min

Recover - if you already engaged with the scam

---

Pick the step below that matches what you did. If multiple apply, work through them in the order they appear - the steps are arranged from lowest to highest risk.

7

You only clicked a link (didn't enter anything or download anything)

Scenario: clicked link only10 min

Close the page right away. Don't enter any information, even if the page looks legitimate.

• Clear your browser cache and cookies for the last hour - Chrome/Edge: Ctrl+Shift+Del → Last hour → check Cookies and Cached files
• Run a quick scan with Combo Cleaner in case the page tried to drop a file silently (drive-by download)
• Update your browser to the latest version - most drive-by exploits target outdated browsers
• Watch for new browser pop-ups, redirects, or unfamiliar notifications over the next few days

Why this matters

Modern browsers block most drive-by attacks, but a single click on a phishing page can still be enough on an outdated browser or unpatched plugin. A quick scan catches anything that landed silently.

8

You opened an attachment or downloaded a file - run a full malware scan

Scenario: opened attachment⚠ Highest risk60–90 min

Opening an attachment is the most common path to actual infection. Treat the system as compromised until the scans below come back clean. Work through these sub-steps in order:

8.1Disconnect from the network

Unplug Ethernet and turn off Wi-Fi. If the attachment was an info-stealer or remote-access trojan, this stops it from sending data out or receiving commands. Keep the network off until you've booted into Safe Mode (next step) - you'll reconnect there briefly to download the scanners.

8.2Boot into Safe Mode with Networking, then download the scanners

Windows 11: Settings → System → Recovery → Advanced startup → Restart now → Troubleshoot → Advanced options → Startup Settings → Restart → press 5 or F5.

Windows 10: hold Shift, click Power → Restart → Troubleshoot → Advanced options → Startup Settings → Restart → press F5.

Once Safe Mode has loaded, turn Wi-Fi back on and download Combo Cleaner (used in 8.4) and Microsoft Safety Scanner (used in 8.5). Safe Mode loads only minimal drivers, so most malware can't auto-run while you're getting the tools. Save both installers to your Desktop.

8.3Run Microsoft Defender Offline

Reboot to normal Windows. Open Windows Security → Virus & threat protection → Scan options. Select Microsoft Defender Antivirus (offline scan) and click Scan now. The PC restarts into a stripped-down environment and scans the disk before Windows fully loads - this is what catches rootkits and bootkits.

Recommended antivirus

Combo Cleaner

VB100 certified. Includes anti-trojan, registry/persistence scanning, and anti-spyware in one pass. The 7-day free trial is available.

Download Combo Cleaner

8.4Run a full Combo Cleaner scan

Install Combo Cleaner and run a full system scan (not the quick scan). Let it complete fully, review what it found, and apply the recommended actions. Combo Cleaner will quarantine known trojans and remove their persistence in the registry.

8.5Run Microsoft Safety Scanner as a second-opinion scan

Download Microsoft Safety Scanner (MSERT.exe). The binary expires every 10 days, which means every download has the latest signatures. Run a full scan after Combo Cleaner to catch anything one engine alone might miss.

8.6Reset browsers and clear notification permissions

Many email-borne trojans drop adware that hijacks browsers. Reset each browser you use:

Chrome: chrome://settings/reset → Restore settings to their original defaults. Then chrome://settings/content/notifications - remove unfamiliar sites.

Edge: edge://settings/reset. Then edge://settings/content/notifications.

Firefox: about:support → Refresh Firefox.

8.7Re-enable Defender, Tamper Protection, and update everything

Open Windows Security → Virus & threat protection → Manage settings and confirm Real-time protection, Cloud-delivered protection, and Tamper Protection are all on. Then run Settings → Windows Update → Check for updates and update browsers and applications.

Important

If the scans keep finding new threats on each run, or files reappear after deletion, you may have a deeper compromise that needs a clean Windows reinstall. See pcrisk's full manual malware removal guide for the extended procedure (Process Explorer, Autoruns, hosts file inspection).

9

You entered credentials on a fake login page

Scenario: shared password⚠ Act fast20 min

Assume the attacker has your password and is using it right now. Speed matters.

1. Change the password from a different, known-clean device (your phone is fine if it's not infected). Don't reuse the old password anywhere else.
2. Enable two-factor authentication if you haven't already. Prefer an authenticator app or hardware key over SMS.
3. Sign out of all sessions - most platforms have a "sign out everywhere" option in security settings, which kicks the attacker out.
4. Review recent activity - look for unfamiliar logins, new devices, forwarding rules, or app permissions. Remove anything you don't recognize.
5. Check your other accounts - if you reused that password anywhere else, change it there too. Check your exposure at haveibeenpwned.com.
6. Update security questions - the attacker may have seen the answers in your account profile.

Why email comes first

If you only have time to change one password, change your primary email password - it's the recovery hub for every other account. An attacker who controls your email can reset everything else.

10

You sent money or shared bank, card, or ID details

Scenario: financial loss⚠ Contact bank now30 min

Time is the single biggest factor in recovering money. Banks can sometimes recall a wire or reverse a card transaction within the first few hours.

1. Call your bank or card issuer immediately. Use the number on the back of the card, not any number from the scam email. Ask them to freeze the card, reverse the transaction if possible, and flag the account for fraud monitoring.
2. If you sent a wire transfer or used a money-transfer service (Western Union, MoneyGram, Zelle, Wise), call them directly and request a recall. Some can be reversed within minutes if reported fast.
3. If you sent cryptocurrency or gift cards, recovery is unlikely - but report it anyway, since law enforcement tracks these patterns.
4. File a police report. You'll need the report number for any insurance, bank, or credit-bureau claim. Save the report number.
5. File with the right authority for your country:
   • US: ic3.gov + reportfraud.ftc.gov
   • UK: reportfraud.police.uk (Report Fraud, the successor to Action Fraud; 0300 123 2040)
   • Canada: antifraudcentre.ca
   • Australia: scamwatch.gov.au
   • EU: your national CERT or police cybercrime unit
6. Set fraud alerts on all major credit bureaus if you shared any ID details. US: Equifax, Experian, TransUnion. UK: Experian, Equifax, TransUnion (Cifas Protective Registration is a stronger option).
7. Save all evidence - the original email (with full headers), screenshots of the fake site, transaction records, any phone numbers or chat logs.

Phase 4~ 15 min + 30 days

Verify & monitor

---

11

Final scan and startup-app check

15 min

Reconnect to the network and run one final full scan with Combo Cleaner, followed by a Windows Defender quick scan. Then open Task Manager (Ctrl + Shift + Esc) and switch to Startup apps - disable anything unfamiliar.

Make sure Windows, browsers, and any applications you use are fully up to date. The infection vector that worked on you once usually involves outdated software.

12

Monitor accounts and credit for 30 days

5 min/day · 30 days

Most fraud follow-ups land in the first month. Until that window closes, keep watching:

• Bank and card statements - daily for the first week, then weekly
• Email - watch for password-reset confirmations or login alerts you didn't trigger
• Credit report - US: free at annualcreditreport.com; UK: Experian, Equifax, TransUnion all have free tiers
• Breach alerts - sign up at haveibeenpwned.com to be notified when your email appears in new leaks

If anything new appears in any of those, treat it as a continuing compromise: change passwords again, contact the bank again, and update the police report.

Important: If you didn't click anything, didn't reply, and didn't open any attachment, your computer is not infected - just delete the email and move on. If you opened an attachment or downloaded a file, run an automated scan with Combo Cleaner and Windows Defender and stop there. That path catches the vast majority of email-borne malware without the risk of breaking Windows by deleting the wrong file.

Frequently Asked Questions (FAQ)

Why did I receive this email?

Thousands of users receive identical spam emails; they are not personal. Cyber criminals distribute these letters in large quantities with the hopes that at least some of the recipients will fall for their scams.

I have read this spam email but didn't open the attachment, is my computer infected?

No, merely reading a spam email will not initiate any infection processes. Malware download/installation is triggered when the attachments or links present in this mail - are opened/clicked.

I have downloaded and opened the file attached to this spam email, is my computer infected?

Whether an infection was triggered - depends on the file's format. Executables (.exe, .run, etc.) infect systems nearly without fail. However, document formats (e.g., .doc, .xls, .pdf, etc.) may require additional actions (e.g., enabling macro commands) to begin downloading/installing malware.

Will Combo Cleaner remove malware infections present in email attachments?

Yes, Combo Cleaner is capable of detecting and eliminating most of the known malware infections. However, it must be emphasized that performing a full system scan is crucial - as high-end malicious programs typically hide deep within the system.