Malicious PDF — malware analysis report

Static analysis result for SHA-256 6077e4905a7c2f46…

MALICIOUS

PDF

73.8 KB Created: 2021-09-07 20:19:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a67e1365e23780d5068462fc7fcb25a8 SHA-1: fb1f45374dfbbf172ecc59ed5c8c30f6d73bbcf0 SHA-256: 6077e4905a7c2f46e259754522a1956263da7acd9ee4d2bd723d73924b5c9585
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, but the presence of external URIs and the overall heuristic profile point towards a phishing or credential harvesting attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://medvor.ru/uplcv?utm_term=credit+information+report+iba+format+pdf PDF link annotation
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/ob43jnbc5voav4hu8k3h0pj3dj/sigivufodavovevuxunebilav.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/161211b9c92c8a---68877555057.pdfIn PDF document text
    • https://gilbertems.com/videos/file/98440517571.pdfIn PDF document text
    • https://aramlasmerok.hu/uploads/file/22792539888.pdfIn PDF document text
    • http://eskuvoiiranytu.hu/blog/file/84990228040.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/7fgan5gm65lt0j2sl67aih0k7b/75397385976.pdfIn PDF document text
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/d5d5f94d44f2cdae95fad7a3b7f71311/4364777799.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/zevupewexuvalenijezi.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a531986dc2d---92311615140.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095e08736b66---fogumovogupo.pdfIn PDF document text
    • http://e-sportis.com/images/upload/39422845989.pdfIn PDF document text
    • http://tlumacz-lipno.pl/pdrzewiecki/files/93163433293.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843e80c08ed---bovodegixovikifoxe.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/bf7t9705qjolpd4f60amfhmr5t/24859858938.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/90457810779.pdfIn PDF document text
    • http://okna-dvere-online.cz/media/upload/upload/file/3539324592.pdfIn PDF document text
    • https://24emk.ru/ckfinder/userfiles/files/jisirizi.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a22aff5c833---62351051706.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffebd322a1---fepujarerirebewib.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f53416e142---51254549609.pdfIn PDF document text
    • https://abeess.com/userfiles/file/tanelurirebinolavatu.pdfIn PDF document text
    • http://charivne.info/images/file/41270921646.pdfIn PDF document text
    • http://jkmdc.com/aversystem.com/userfiles/file/30002356752.pdfIn PDF document text
    • http://greece-ex.com/images/blog//file/vebirupozuxaterexeladufu.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/dexosugewuxugowupulonu.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_off0000c0be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0BE 10616 bytes
SHA-256: d96b3e3cd01b82d75870a0c78125a036b68ec7b86bd3a6d3d72d6c4b72f24107
font_01_sfnt_off0000d8bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BB 16132 bytes
SHA-256: 326417ec9a1cb115ce70dcde855e123d28dcf403d266538becb2355c96e33c6a
font_02_sfnt_off0001019b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1