Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9329c681b735bc8…

MALICIOUS

PDF

109.7 KB Created: 2021-07-23 05:00:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1ee54fca27aca962c2692044d7519d93 SHA-1: 515a24a1af0d741654887781cb07d5626b4a389b SHA-256: a9329c681b735bc89f1368c71543d6322b7b41261ecc98d273c7ef5384673b5b
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. No scripts were extracted, but the structure and URL patterns are consistent with a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9881

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://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160cf1166a2ceb---51668534227.pdf In PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c4cc8075e75---rusaxatedetukig.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/89394349470.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/16079334171155---jodesok.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160874594aa978---zinegidibonilodulipep.pdfIn PDF document text
    • http://msamericapageant.com/clients/873634/File/13396468180.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af7a83b2e13---tifexepi.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160861e3864b4f---2388875780.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/1862716563.pdfIn PDF document text
    • http://moon-villa123.com/CKEdit/upload/files/72248167505.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/46bd96fa6fc4508b80be0878958c9ae9/79940102039.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/d117c8c1936cd5ab83db868e90206fda/77577528055.pdfIn PDF document text
    • http://brukbet.com/user_images/file/tununaseludon.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/1daba45ede3c9a21333979a6320ba2e3/81956030453.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607599d953d8a---fegosawijirosafuxirem.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/1vcnfkf6mh2a48r5s2rm9q5fk4/gidufodetubusavuza.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/zokazozago.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609acc9b3b1a7---44785472368.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/9a5c0fa0b4726b95c928766c28f5b1ff/35701240442.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/g576dkf9odbbaim63rd3o98kqf/xilezobe.pdfIn PDF document text
    • https://www.mnogotrop.com/ckfinder/userfiles/files/kikosajosudoliki.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/61381327783.pdfIn PDF document text
    • https://mfdesign.hu/files/file/97619848212.pdfIn PDF document text
    • https://turkihale.com/userfiles/file/84884317904.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa61e0edb9---78102077450.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=wow+brewmaster+monk+talentsPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/0aedc998a231e7ce787e8d95bf64193c/bepamemuxu.pdfIn PDF document text
    • 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_off00014832.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14832 19160 bytes
SHA-256: 4427865f216eb4f5b0f93f15055438671690792d1f1d475f3a36eb3987d025d2
font_01_sfnt_off0001794d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1794D 10488 bytes
SHA-256: fb8a174484668174523c30f946447d63b0cb5cc9f251bcceb52763069b0812b2
font_02_sfnt_off0001913d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1913D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1