Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fb43c3f9f6e6c9c…

MALICIOUS

PDF

79.2 KB Created: 2021-09-19 06:42:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d8069df56c827c6aa03c774dc7891d6f SHA-1: c2dd859a3564a0bec7f13d99c66478e904ab1d84 SHA-256: 4fb43c3f9f6e6c9cf71a76a6d913c543333d8d5d1fa81c8aabf32ac61d3e02af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a large number of embedded URLs, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of 'utm_term' in one URL indicates a potential phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://ketchas.ru/uplcv?utm_term=video+poker+apk+download
    • http://podwierzba.eu/ckfinder/userfiles/files/mujefovunotuv.pdf
    • http://busangh.com/attfile/fckimg/file///2021091520958_175815004.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bebd92eed---34659959266.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/3c863768f4359d811cdea084347ed054/boturoduzixedite.pdf
    • http://viquadro.com/userfiles/files/zuwugemojekufogunolabijiw.pdf
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/30089972510.pdf
    • http://telecycling.org/files/file/5400150931.pdf
    • http://ducnhua.com/upload/files/55295637269.pdf
    • https://stopserv.ru/files/file/jolef.pdf
    • https://hotelcorona.ro/files/47172019021.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16138721fb741b---42541165575.pdf
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/gevebozixapezifusipan.pdf
    • http://kooijobs.in/ckfinder/userfiles/files/9406281618.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16143793e41753---8319843194.pdf
    • http://dailygameresult.com/editor/UserFiles2/files/tunej.pdf
    • https://ms2oke.com/contents/files/75326895732.pdf
    • http://irvinenott.co.uk/ckfinder/userfiles/files/7506532935.pdf
    • http://asid.rw/userfiles/file/gepegisoti.pdf
    • http://polaryachtmanufactory.com/res/wysiwyg/file/fatimegukedovonexowaras.pdf
    • http://gro-felix.si/uploads/wezaw.pdf
    • http://santabruna.cl/upload/file/21897813403.pdf
    • http://vanillasky-ch.com/images/files/43675985686.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d190.bin
64b7678bb050fe23ba236db071261efa1b06614a64a0fa8bf823eab3f318a4a8
pdf-font-stream PDF embedded font (sfnt) at offset 0xD190 18008 bytes
font_01_sfnt_off00010064.bin
3cb04fe2cd13092e9f89091c83603f974766f34862a216c0ed495cf3c621f246
pdf-font-stream PDF embedded font (sfnt) at offset 0x10064 10268 bytes
font_02_sfnt_off00011793.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11793 16792 bytes