Quishing (QR Phishing)

Quishing (QR code phishing) is a rapidly evolving cyber threat that exploits the convenience of QR codes to trick users into compromising their security. By embedding malicious links within seemingly harmless QR codes, attackers bypass traditional email filters and direct victims to fraudulent websites or malware downloads. This social engineering tactic capitalizes on the widespread use of QR codes in business operations, making organizations vulnerable through both corporate and personal devices.

Quishing is a social engineering attack where cyber criminals exploit QR codes—two-dimensional barcodes that store data both horizontally and vertically—to redirect victims to malicious websites or trigger malware downloads. Unlike traditional phishing, which relies on text-based links, quishing uses QR codes to bypass email security filters and exploit user trust in this widely adopted technology.

QR codes are machine-readable matrices capable of storing up to 7,089 numeric characters or URLs, accessible via smartphone cameras or scanning apps. Their design includes error-correction features, allowing them to function even if partially damaged. While legitimate uses range from contactless payments to marketing campaigns, their opacity (users can’t preview the embedded URL) makes them ideal for exploitation.

Quishing attacks are carried out in a systematic process. Attackers follow a systematic approach:

1. Malicious QR code creation: Free online tools generate QR codes linked to phishing sites or malware-hosting domains.
2. Distribution: Codes are embedded in phishing emails, fake invoices, public posters, restaurant menus, or even overlayed on legitimate QR codes.
3. Social engineering lures: Messages urge immediate action, such as “Scan to unlock a discount” or “Verify your account.”
4. Exploitation: Scanning redirects users to spoofed login pages, credential harvesters, or malware downloads. For example, a 2023 attack mimicked corporate invoices, directing employees to fake payment portals.

By blending physical and digital attack vectors, quishing poses a multifaceted threat to organizations and individuals alike.

Quishing attacks thrive at the intersection of physical and digital spaces, exploiting both human curiosity and organizational workflows. Cyber criminals strategically deploy malicious QR codes in high-traffic or high-trust environments to maximize success rates. Key targets include:

• Public venues: Tampered QR codes appear on restaurant menus, parking meters, retail store posters, or event flyers—often promising discounts, WiFi access, or exclusive content.
• Phishing emails/SMS: Attackers impersonate banks, government agencies, or corporate vendors, embedding QR codes in fake invoices, “account verification” alerts, or shipping notifications.
• Product labels: Malicious actors replace legitimate QR codes on product packaging with links to counterfeit websites or malware downloads.
• Shared documents: QR codes hidden in internal PDFs or spreadsheets, masquerading as surveys or training materials.
• Targeted industries: Energy, manufacturing, insurance, and financial services—sectors with complex supply chains and high-value transactions.

For example, a 2024 campaign targeted restaurant chains by overlaying malicious QR codes on printed menus, redirecting diners to credential-harvesting pages mimicking loyalty programs.

Quishing exploits the trust users place in QR codes, but organizations can mitigate risks by combining user education, technical safeguards, and proactive policies. Below are key strategies to defend against these hybrid threats.

User Vigilance Best Practices

• Verify QR code sources: Confirm legitimacy with the sender via a separate channel (e.g., phone call) before scanning codes in emails, texts, or public spaces.
• Inspect URLs previewed by scanners: Check for HTTPS encryption, misspelled domains (e.g., “arnazon.com”), or suspicious shortened links.
• Avoid sharing sensitive data: Never enter credentials or payment details after scanning a QR code unless the site’s authenticity is confirmed.
• Use secure QR scanner apps: Opt for antivirus-integrated apps that flag malicious links.

Organizational Security Measures

• Phishing simulations: Conduct regular quishing attack drills to test employee response rates and identify gaps in awareness.
• Multifactor authentication (MFA): Enforce MFA across critical systems to neutralize the impact of stolen credentials from quishing sites.
• Email security upgrades: Deploy DMARC, SPF, and DKIM protocols to block spoofed emails containing malicious QR codes.
• Endpoint protection: Install anti-malware tools with real-time scanning to detect and quarantine payloads delivered via quishing links.
• Zero trust architecture: Restrict network access to verified users and devices, limiting lateral movement if a breach occurs.

Policy-Driven Safeguards

• Least-privilege access: Restrict employee permissions to minimize damage from compromised accounts.
• QR code usage guidelines: Ban scanning codes from untrusted sources in corporate communications.
• Tamper-proof physical codes: Audit public-facing QR codes (e.g., posters, product labels) for signs of overlay attacks.

Training Priorities

• Spotting social engineering: Train teams to recognize urgency-driven lures like “Scan to avoid account suspension.”
• Reporting protocols: Establish clear channels for employees to flag suspicious codes without fear of reprisal.

By embedding these practices into cybersecurity frameworks, businesses can reduce quishing’s success while maintaining operational agility.

Technology is pivotal in countering quishing attacks, blending advanced detection tools with proactive organizational strategies to neutralize QR code-based threats. Below are key technological and procedural defenses enterprises can deploy.

Security Solutions

• QR code analysis engines: Specialized email security solutions use computer vision models to scan emails for QR codes, decode embedded URLs, and assess their risk using machine learning trained on decades of phishing data. For example, Cloudflare processes QR codes in real time, crawls decoded links, and cross-references them against threat databases to block malicious content.
• Inline sandboxing: Platforms like Proofpoint extract QR codes from attachments (e.g., PDFs) and simulate URL interactions in isolated environments to detect malware or credential harvesters before delivery. According to Microsoft, this pre-delivery scanning blocked ~1.5 million daily quishing attempts in 2024.
• AI-powered threat detection: Microsoft Defender for Office 365 employs image extraction to identify QR codes in emails, analyzes URL structures via ML, and blocks suspicious links using heuristic rules.

“Legacy email security providers and most API-based email security tools have a very difficult time detecting these attacks,” writes Tim Bedard, Principal of IBM Expert Labs Sales. “That’s because these tools scan email messages for known suspicious links—they don’t scan images for links that are hidden inside malicious QR code images.”

Organizational Measures

• Secure QR code generators: Use enterprise-approved tools with embeddable expiration dates and domain allowlisting to ensure codes link only to vetted URLs.
• Network segmentation: Isolate IoT devices and guest networks from critical systems to contain breaches triggered by quishing-linked malware.
• API security for third-party integrations: Monitor QR code-driven workflows (e.g., vendor portals, inventory systems) for anomalous API calls indicating credential misuse.
• Digital signatures for QR Codes: Implement cryptographic tagging (e.g., QR-Code 2.0 standards) to verify authenticity and detect tampered codes in physical spaces.
• Threat hunting with UEBA: Deploy User and Entity Behavior Analytics to flag unusual post-scan activity, such as sudden data exports from cloud storage.

Bedard encourages leaders to “Defend your organization from emails sent from potentially compromised vendors and partners. Proofpoint Supplier Threat Protection uses advanced AI and the latest threat intelligence to detect the supplier accounts that have been compromised and prioritize any that should be investigated.”

Training and Human Vigilance

“Your employees and customers are your first line of defense. Make sure they get security awareness education about all types of phishing attacks,” adds Bedard.

• Cybersecurity simulations: Proofpoint’s phish simulation tool runs adaptive QR phishing drills, tailoring scenarios to employee roles and skill levels.
• Interactive learning: Security Awareness Training platforms redirect employees who fail simulations to micro-trainings explaining QR code red flags, such as mismatched URLs or urgency-driven lures.
• Reporting culture: Establish easy channels for employees to flag suspicious codes. Proofpoint’s integration of AI-driven context analysis with user reporting helps identify novel attack patterns.

By combining cutting-edge detection tools with rigorous training, organizations can stay ahead of quishing’s evolving tactics while fostering a security-first mindset across teams.

Proofpoint delivers end-to-end protection against quishing through advanced threat detection, pre-delivery sandboxing, and user-centric security training. Its proprietary QR code scanning engine decodes embedded URLs in emails and attachments, analyzing them in real time via behavioral AI and threat intelligence from 230,000+ global customers. Pre-delivery sandboxing isolates suspicious links, blocking malicious QR codes before they reach inboxes—a critical edge over post-delivery solutions.

For enterprises, Proofpoint’s Security Awareness Training integrates quishing simulations, auto-enrolling vulnerable users in adaptive learning to combat evolving tactics like QR-based credential harvesters. Multi-layered defenses, including NexusAI and URL sandboxing, neutralize 99.99% of email threats, while integrations like PhishAlarm empower employees to report suspicious codes seamlessly. By combining machine-speed analysis with human vigilance, Proofpoint safeguards organizations from quishing’s hybrid risks, protecting 87% of the Fortune 100. Contact Proofpoint to learn more.