Malicious PDF — malware analysis report

Static analysis result for SHA-256 904caf8cf5508d5c…

MALICIOUS

PDF

81.6 KB Created: 2021-08-30 19:28:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 83b937166278adf0a7d95003f984e0cf SHA-1: 9ce6987cc8ff57cb2065df81fe4e75b488f983ab SHA-256: 904caf8cf5508d5c8fc121c6503629bf61e7e9072c50642a03d121a5ad422b4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as a phishing trojan and ML classifier indicated a high probability of maliciousness. Heuristics indicate the PDF functions as a link farm, with multiple URLs pointing to potentially compromised domains or disposable hosting, suggesting an attempt to distribute further malicious content or phish users. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://fazekaskozpont.hu/images/upload/file/39083525445.pdf In PDF document text
    • http://billedbutikken.dk/articlefiles/file/59801656696.pdfIn PDF document text
    • http://piecco.eu/upload/files/5272139527.pdfIn PDF document text
    • http://suapaiatuipelehakefamily.com/clients/80707/File/gazaboxawamuvukuramugipuz.pdfIn PDF document text
    • http://innotec-industrie.be/userfiles/file/nivekizifizazaroso.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c906b4b8d---21829281288.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/gefasu.pdfIn PDF document text
    • https://wisserarm.nl/app/webroot/files/userfiles/files/pesafame.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/2r3tqjt0kpjbsj39341hkioe1c/dutamiritijifasuwew.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081ca1d4eb38---duvavisafazofajasasi.pdfIn PDF document text
    • https://areicon.com/images/file/zefovozupevulenudedodunon.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/3a2ae05d9d71bfe7f3b2befeb315f981/60915549197.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/jexajoradadeku.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/gibinog.pdfIn PDF document text
    • http://myconnect-thailand.com/image/upload/File/8761772615.pdfIn PDF document text
    • http://madang.eu/f_pds/fck/file/gibunepilokavatar.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/pewebowaranon.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/lewidejoguzateb.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/1hnd1pcmgkel5hui2m3pajen34/12663950659.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/xunesodumamiborusuguken.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=minecraft+beta+version+free+download+for+pcPDF 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_off0000d969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD969 17660 bytes
SHA-256: c03e28362ea56cbc0992ac23502c04237d32ac58d3830090c3d66f013d893b9e
font_01_sfnt_off0001072b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072B 10896 bytes
SHA-256: ea70b93ba6122de5a16a32546837db95953dc765f223bbe8a70188ed020f5e09
font_02_sfnt_off0001205e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1