Malicious PDF — malware analysis report

Static analysis result for SHA-256 a81e61bec9990224…

MALICIOUS

PDF

87.5 KB Created: 2021-06-27 08:29:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: f855612e2d635e93ec33193760cdbd57 SHA-1: 10f2b6431b45e6c9f7ea0f20f8485c84ae7a55b3 SHA-256: a81e61bec9990224b1104b244bb6b1730856279b5466bd5e1ce878b86192ecf2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links to compromised WordPress upload directories and disposable hosting, indicating it functions as a link farm. The primary purpose appears to be directing users to potentially malicious or phishing websites, likely distributed via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160928a842ff07---60867045571.pdf In PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//75764504558.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160a5491f41d5f---96676604373.pdfIn PDF document text
    • https://businessservicesuk.com/userfiles/file/58428115842.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/cc1c4e86c84c218e4a3f4c879096c468/8449754617.pdfIn PDF document text
    • http://worldwidefilipinoalliance.com/uploadedFiles/files/42183444404.pdfIn PDF document text
    • http://schooldistrictservices.com/clients/f/f6/f6ab1571d2cdf5e569af7b76e288b17c/File/64401188226.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/felumoku.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607d317ecd76c---92057196350.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/49c598767bb748e46a67f360aa37e892/36397695090.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-6-26/20210626101851597842.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/f8a53180718cc88bb7f811e19cfe050c/59595849676.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/96420431b7eab7f76c481bf55d21ea4a/36754054259.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608faf411d56a---12018731712.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/45317737054.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c94c26ab2da---fifezok.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/pekivixan.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/razusudoru.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/bb03810af7177db4d4367e540a218528/juvonowukemi.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d901a75d25b90168c7a4a94c52ca8957/gebivixetes.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/71888113450.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3873a837b6---tejosunog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=best+app+for+viewing+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED5B 18636 bytes
SHA-256: 0c3ca1a13b2d4f968234a9a99cc9198efc44eaf6c2b4e00f804ea368b45756ad
font_01_sfnt_off00011e71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13688 10832 bytes
SHA-256: dc704a576428ac9f30f5439bca8ab9c5eac4303cf69afc3a57c6ab0d782526c6