Malicious PDF — malware analysis report

Static analysis result for SHA-256 248bd4f62ffd63be…

MALICIOUS

PDF

313.0 KB Created: 2021-07-07 21:44:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8cf4723bfb786b727840b54d3eaf3337 SHA-1: 2e3d883b2cc68723bd49a77eee29cff869c73abb SHA-256: 248bd4f62ffd63be4e1443584ed99701882ff33336104a81c8d34222eda0a5cd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, with at least one pointing to a compromised WordPress upload directory, suggesting it's part of a link farm or phishing campaign. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to redirect users to malicious content hosted on compromised websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9767

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/d8pkbh5t2pnm4112s9fj0372s2/tebadegutuxejoguzinunof.pdf In PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a58a27a8055---vipipukizen.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/powejakokekelizi.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/lusofutububegele.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160e033833db57---2541323993.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/68363700547.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/72ca514fa76290bd128681beae1bb587/liseveworuxebiwa.pdfIn PDF document text
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/4865aa6da8a7a646f4d5bea1396e0b30/kobem.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/1vcuhmq3pt93cposqpe4914m28/37519773449.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/8pampo07k002pd37ttkgr8rac0/23901298706.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/gusobafejoxejeximo.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608d12bae8ada---godivoboxefa.pdfIn PDF document text
    • http://stolizstekla.ru/userfiles/file/95435453964.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/f06d58238bfb534799ecb76cb3e721da/58072805550.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/fagup.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a86cecd444a---bikiwatebita.pdfIn PDF document text
    • https://ltanimalpark.com/wp-content/plugins/super-forms/uploads/php/files/15d1e35bb8e66dbec7864b5f800c40c7/xukeris.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5b5c7fbb2---93676685548.pdfIn PDF document text
    • http://eprdel.cz/userfiles/file/jaxazolef.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/tixotenavowure.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cac640c916---7212341492.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/41296581730.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a4497281a2a---wolebinisewif.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079917cd80c1---nafuwodetajug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=dr+ginger+pace+herndon+sumrall+msPDF 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_off0004766c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4766C 17492 bytes
SHA-256: 37320c326851d91c0d6cd0be495a2998d1624c61436b3ad9610a291bc1e7cec9
font_01_sfnt_off0004a44e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4A44E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0004bc65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4BC65 10964 bytes
SHA-256: bbf0900ab44620b69d8001964074c629c456b9deb77dad0db230d8aef50d9134