Malicious PDF — malware analysis report

Static analysis result for SHA-256 b33638cd289fbdd6…

MALICIOUS

PDF

102.8 KB Created: 2021-06-27 00:41:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 793fe1860ba08311c778840577c37a55 SHA-1: db0d682b20cad4a271b28a9f26ecba8c3bc981b3 SHA-256: b33638cd289fbdd6e2458dc87df13ec45aeb083b36659df52ac05e20141461a1
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097e938d99cf---mokawagox.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607335f393731---77071074462.pdf
    • http://monkey-do.net/userfiles/file/ninuvobakupolunaf.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/t4ov9npsr7bhvrjs96c2eb82u7/luvowuxef.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607777cb2f373---66634054876.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a41e2752e85---xosupuxafejusujikef.pdf
    • http://nuestratierrapremios.com/campannas/file/86723721535.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607425cfc2951---22951288351.pdf
    • http://tasteofruraleurope.eu/upload/File/rebubafudulusidexi.pdf
    • http://vidol.nl/userfiles/file/bodoman.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1d56cd7643---91465817190.pdf
    • http://aarogyamedico.com/userfiles/file/lugakutikoxonutugazized.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16076617d7fe21---pobopuvelegipukagi.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/4c44f351ab65b259042fdd51fa3c9fe0/56444489493.pdf
    • http://humanitool.ru/userfiles/file/gudajojezuxeja.pdf
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/7d1e6a0b851a6a0c310f67f88df23d39/lovowexilaku.pdf
    • https://kermiradiatoriai.lt/images/files/70863472528.pdf
    • http://e-skala.pl/userfiles/file/tazapatolon.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-5-7/20210507010743208208.pdf
    • http://anhuifan.com/upload_fck/file/2021-4-30/20210430183637704853.pdf
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/f8d127cccabd56c7b6fdba936e12d70b/najoxoga.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/e7pcf9ohe0i5e3nltb8mgsdksr/54710933569.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608938c74daf2---5715814762.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc7b4cf72e---8797918750.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=additive+primary+colors+of+light
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012b21.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B21 16792 bytes
font_01_sfnt_off00014338.bin
9704099b703ffba6cd65dde35ab18378110697c528b35b65ff54c5fa2ef0ab9e
pdf-font-stream PDF embedded font (sfnt) at offset 0x14338 11124 bytes
font_02_sfnt_off00015d0a.bin
e5bbea6742c81ff41a640bc19956d5f242e156630a19bbc33c81fb1cf3fa6840
pdf-font-stream PDF embedded font (sfnt) at offset 0x15D0A 17836 bytes