URGENT: Your Costco Rewards — $500 Member Bonus Expires Today Promotions


        Dear valued Costco member,

        
          Our security team has flagged urgent activity on your account.
          You must verify your membership within the next 24 hours to
          claim your $500 annual reward before it is forfeited.
        

        
          [SIGNAL] image-wrapping anchor — href points to
          secure-costco-rewards.xyz, a suspicious TLD
          brand-mismatch.
        
        
          
            
          
        

        To claim your reward, please visit your member portal below:

        
          [SIGNAL] text/href mismatch — visible text says
          www.costco.com/rewards, href goes to
          secure-costco-rewards.xyz/claim.
        
        
          
            www.costco.com/rewards
          
        

        
          [SIGNAL] button-wrapping anchor — link contains a
          <button> CTA.
        
        
          
            
          
        

        
          [SIGNAL] redirect-chain trap — benign-looking short URL;
          Uses a suspicious TLD (.click).
        
        
          Confirm your shipping address via our partner tracking portal:
          
            costco-rewards.click/u/eJwNy0E...
          
        

        
          [SIGNAL] brand impersonation — anchor text says
          "Costco Member Services", href is on lookalike
          c0stco.com.
        
        
          Questions? Contact
          
            Costco Member Services
          
          for immediate assistance.
        

        
          [SIGNAL] scam phone number — toll-free number in body
          surrounded by keywords "urgent", "verify", "security team".
        
        
          Or call our security team immediately to verify your
          membership at
          1-800-555-0199.
          This is an urgent matter and must be resolved today.
        

        
          [SIGNAL] remote-access link — "tech support" button
          pointing at teamviewer.com.
        
        
          If you need assistance, our support team can connect to your
          computer through our tech support portal:
          
            Start Remote Support Session
          
        

        
          [SIGNAL] dangerous download — anchor href ends in
          .exe.
        
        
          
            Download your reward voucher (.exe)
          
        

        
          Thank you for being a loyal Costco member. We look forward to
          continuing to serve you.
        

        
          Sincerely,

          The Costco Member Services Team
        

        
        
          
          
        

        
        
          Costco Wholesale
          999 Lake Drive, Issaquah, WA 98027

          
            [NEGATIVE CONTROL] own-brand social links — the page
            brand text is "Costco" so W5's own-brand suppression should
            prevent these social links from being flagged.
          
          
            f
            X
            in
            Y
            IG
            @
          
          
            © 2026 Costco Wholesale Corporation.
            Privacy ·
            Unsubscribe
          
        

        
        
          Negative controls — these should NOT be flagged
          
            Real costco.com rewards page
            — legitimate href on the same brand as the page.
          
          
            Wikipedia: Costco
            — plain informational link.
          
          
            GitHub homepage
            — common safe anchor.
          
          
            Plain text mention of google.com
            as an unrelated search engine — no brand conflict, no suspicious tokens.
          
          
            help@costco.com
            — mailto: should be ignored entirely.