Malicious PDF — malware analysis report

Static analysis result for SHA-256 21c8c5ae75f8b89f…

MALICIOUS

PDF

71.2 KB Created: 2021-09-17 02:47:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 478617b4321d3f195b95695346d6525d SHA-1: 26ec5baf1f25ebb8b30b6389d0653479c4818f2f SHA-256: 21c8c5ae75f8b89fa230c7d8a2b41615e18d6a5e2273978f11aa58b44aad2df8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm with 28 links pointing to 20 distinct hosts, including compromised CMS upload storage. The embedded URLs suggest a phishing or redirection scheme to distribute further malware or lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • 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://energooptima.hu/upload/File/56100479575.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142149ca1650---gexagagogumojozagusem.pdfIn PDF document text
    • https://pinkrali.com/calisma2/files/uploads/88023675253.pdfIn PDF document text
    • http://dealershop.es/userfiles/file/teziwixed.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614161fbbe985---22587641720.pdfIn PDF document text
    • http://simsvizag.com/contentimages/file/41271199006.pdfIn PDF document text
    • http://lawyersmarketingusa.com/user_upload_image/file/In PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/7e8e5b918fd04d3c36845796d3ca559e/mibifemufutu.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/vuxiwokivad.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16133436f72a3f---53025582377.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/ef265214e71ee902f14e12b0e630e6d3/wakiluvuvesow.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/tudavapuvetepumobejobe.pdfIn PDF document text
    • http://olddieselparts.com/ckfinder/userfiles/files/botibamosatoxebugemikazi.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/34027085108.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/44865807193.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/75339416677.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/36249508998.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wajuf.pdfIn PDF document text
    • http://floramarble.com/uploads/kotejojirepidijopanar.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/17897836718.pdfIn PDF document text
    • http://cdmatik.com/uploads/file/52173880490.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=among+us+online+play+free+no+downloadPDF 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_off0000b618.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB618 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE2A 15676 bytes
SHA-256: 5a6a61384347c2fd9e12a53204f23a4b61db9729f030bcb76c57b25b81059fb9
font_02_sfnt_off0000f5fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FD 11024 bytes
SHA-256: 03e523154c15de6e6e351cf7695dacc529a4faf72c07287dd036d15d8d026fc1