Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4d937f0722756fa…

MALICIOUS

PDF

86.4 KB Created: 2021-06-27 17:48:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: d7a9cfaee7cc77d2b1f77e9f0b792f4c SHA-1: 52e0b424f5ed93bb845b55cfcbf7fe0fb2bb77f7 SHA-256: c4d937f0722756fa08d1d66dd9c49da007f305e935d4f65d32660a34dc970e22
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple compromised CMS upload links further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://hmconcretemixingplant.ru/d/files/21529592165.pdf In PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/aa79bb449d264aa59b5ba123a5b468ef/ruwoxufogovetuzojokeku.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b880ca7f8fb---judivusogubokatalalawud.pdfIn PDF document text
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16077ab49a71ac---81820292663.pdfIn PDF document text
    • https://hanahana.vn/media/ftp/file/monimixes.pdfIn PDF document text
    • http://portalkucharski.pl/app/webroot/media/files/nineluzufuxopu.pdfIn PDF document text
    • http://pastoret.it/userfiles/files/moburorateg.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/be3f5254526549a18e9318eb01bb24f1/peveme.pdfIn PDF document text
    • https://juraganmonyet.com/contents//files/wuzegiguzewunozokimora.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/lu2otdkviqsonr4f2m2d8f7m79/53205677591.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a83e360b8---dujejek.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/sanonosulemu.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607622b342adf---35553903030.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160739c08cdaf2---3234163576.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160763cdbe5d6e---jigonisovitif.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608b82723266e---wakixowunowebemekedunetev.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/sudajitubovupaw.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/04cff83a3b23256de51b842f0a1e3584/13601282339.pdfIn PDF document text
    • https://lienlacanien.com/img_pages/file/557053718.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d65acfd8f---nifukolabexukis.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a4d215854---55375532881.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/cc1a9aee3afe70c791144e64ec8ae9d4/zojanegiwefit.pdfIn PDF document text
    • http://wirheiraten.de/images/file/31355018966.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/rvj9i8pquc6d0783e12nigrr2o/wipek.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/94335050215.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=chemical+formula+of+cement+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_off0000ecce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECCE 10848 bytes
SHA-256: 6abf0ccca36e5806658591717ef24856089cdd6cb9b2f7e03486441ad97a51d2
font_01_sfnt_off000105a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A3 17184 bytes
SHA-256: 9c16e4c285ad4f28e17b304ec8dfb926f66102f4dbff97cc0bdbd3e8c9251319
font_02_sfnt_off000132d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1