Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b43385c2154f20c…

MALICIOUS

PDF

76.3 KB Created: 2021-09-14 21:46:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4df368e5b328aa5de8b2b31ecca2c691 SHA-1: 88b0cbaf0062fc29a342727261b1d365a5fa784e SHA-256: 8b43385c2154f20c69ad0b45d991baa4ba053555765f844d95e5e15d8ff7bc77
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high number of embedded URLs pointing to various domains, many of which are likely disposable hosting, indicating a link farm or phishing campaign. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, but the PDF structure itself is used to host and present these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://catamma.ru/uplcv?utm_term=how+to+increase+internal+storage+with+sd+card PDF link annotation
    • https://terlickodds.cz/www/www/fckphotos/file/vekonozevuguv.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/rigijemarudexojepupawo.pdfIn PDF document text
    • https://mangallagn.com/images/file/sakeroruwurulipabefexotej.pdfIn PDF document text
    • http://studiotecnicodambra.eu/userfiles/files/vivopisa.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/kegazazaboluzonivo.pdfIn PDF document text
    • http://dylogistics.com/userData/board/file/benunanurisawa.pdfIn PDF document text
    • http://kqcme.yiaiwang.com.cn/upload/files/lakerexufukof.pdfIn PDF document text
    • http://cloverdiamond.com/file/87977791975.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/98312876838.pdfIn PDF document text
    • https://peperita.it/writable/public/userfiles/file/dozomafixuxuzuvote.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/tikategezuzilogilaweluw.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/82603178322.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/9230918732.pdfIn PDF document text
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/33298067873.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/93299307765.pdfIn PDF document text
    • http://ourpreferred.com/userfiles/files/wizuj.pdfIn PDF document text
    • http://tentauto23.ru/ckfinder/userfiles/files/58780762463.pdfIn PDF document text
    • http://lateonsettay-sachs.org/userfiles/file/32415719665.pdfIn PDF document text
    • https://eastmangroup.org/ckfinder/userfiles/files/rajafajin.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/ac76d1b70770a04a37b306ce510913ef/nesuvulubinomofokoz.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f70a16a3e5---funowi.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/talomobul.pdfIn PDF document text
    • https://editionsitaliques.com/userfiles/file/rubexa.pdfIn PDF document text
    • http://dominopark.pl/public/upload/ckfinder/userfiles/files/wunilonetodosizuxemobos.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/gumipafokepisupen.pdfIn PDF document text
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/vebaxemurenolozarubijume.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_off0000c5d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5D5 17144 bytes
SHA-256: a7fb7db1b74ccedbd5a4048291cca94a7e9fa3b2a69950745a47977a828f77d3
font_01_sfnt_off0000f23f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A56 10724 bytes
SHA-256: e11517f60851b9a8b6ef89212a16e4fa0080a1640229cbab4632526313b710de