Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb1b0a7639acaf2e…

MALICIOUS

PDF

81.7 KB Created: 2021-09-19 07:29:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 316302b0358c4b88ae070cf7d90e842e SHA-1: 817564016001612b4f63d7e476b943921c207df3 SHA-256: cb1b0a7639acaf2e567613d6a320c047e72aa10a2897d1cfe03b7582b0152417
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614571b4a9bc1---vazudezi.pdf In PDF document text
    • https://almudenafernandez.co/ckfinder/userfiles/Files/54634533844.pdfIn PDF document text
    • https://indiansabroad.uk/userfiles/file/30254638125.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145789c6bc6c---zenaralavamoriwutagipimuj.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/risijuderaniz.pdfIn PDF document text
    • http://njchemland.com/upload/files/26804120792.pdfIn PDF document text
    • http://sowa-architekci.pl/userfiles/files/tutatezubizuretaxa.pdfIn PDF document text
    • https://vegastel.eu/components/com_mijoshop/opencart/image/data/files/78895452517.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/96699169330.pdfIn PDF document text
    • http://cayxaotamphan.net/userfiles/image/file/30649543455.pdfIn PDF document text
    • http://opt-russtd.ru/data_center/upload_pictures/file/47913889222.pdfIn PDF document text
    • http://kruengrangthai.com/files/files/33644599454.pdfIn PDF document text
    • http://adacu.org/userfiles/file/20210908063134.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161444b786c751---14882673660.pdfIn PDF document text
    • https://mayphotocopydogia.com/upload/files/30272557186.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/39554718557.pdfIn PDF document text
    • http://thepducphat.com/upload/files/lugitor.pdfIn PDF document text
    • https://vntdc.com/upload/fck/file/batesadege.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/dovalor.pdfIn PDF document text
    • http://tochuchoinghi.org/files/84774853097.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/xodumef.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/pobad.pdfIn PDF document text
    • https://equalitas.es/userfiles/file/tixezidex.pdfIn PDF document text
    • http://muntepa.com/userfiles/files/xugazepimizozojaparebap.pdfIn PDF document text
    • https://www.mds-horizons.com/upload/files/kozujijaritobu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+add+someone+to+a+call+on+androidPDF 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_off0000d761.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD761 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF78 10608 bytes
SHA-256: eac791a88636afbce62cd8ef45b0546af813418f4e0a2ca38f45743ac671c445
font_02_sfnt_off000107aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107AA 18932 bytes
SHA-256: 8fd64810ad1af815779f1d2edde2a720b101252d105335771f8cca8be075ba00