Malicious PDF — malware analysis report

Static analysis result for SHA-256 79def8c9fb9f1a5d…

MALICIOUS

PDF

83.4 KB Created: 2021-09-19 09:12:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 0ac0e91d61dedfcc9ff7bcde2fb86ced SHA-1: 95a45315bf3c3e954b3e2f088b8cd08291b87464 SHA-256: 79def8c9fb9f1a5decfa03098f43e7091c97da1ad6e2194c998640caa7568659
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and link farm heuristics point towards a lure for users to visit potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://stepweystudy.com/ckfinder/userfiles/files/56941283175.pdf In PDF document text
    • http://vititanon.com/user_img/files/35948067105.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/mepitivas.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c07e3dbb5---89273406321.pdfIn PDF document text
    • http://creationart.hu/files/file/54217142327.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/ponukut.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/29887838281.pdfIn PDF document text
    • https://gdaniec.com/upload/files/welusowujud.pdfIn PDF document text
    • http://ewhamd.net/upFiles/ckeditor/files/girinopidebo.pdfIn PDF document text
    • https://ra7a7p-h3ba7.com/contents/files/foluk.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/gaxuboxu.pdfIn PDF document text
    • https://datxeninhbinh.com/data/dulieu/files/jiniwigu.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142f80a6ba5a---witizadigikozezinis.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/39413326502.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/62960916286.pdfIn PDF document text
    • https://ccskin.com/geektic/files/kubozujamatevupoj.pdfIn PDF document text
    • http://gmkms.net/upfile_editor/2021/files/2364033132.pdfIn PDF document text
    • http://chinawin-consult.com/userfiles/16302903135.pdfIn PDF document text
    • http://sushikyototogo.com/uploads/files/96303145150.pdfIn PDF document text
    • http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/pemakozoxok.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8c3e40e56---51219722972.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161338f377d55c---1811898087.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/45592771558.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/97aaa1e4007442ba0069ad58d6d4c457/xojanozakusekopaxe.pdfIn PDF document text
    • http://fitviewer.biz/files/file/varewatozowujopexozitij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=terminator+salvation+game+download+for+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_off0000e1e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E6 10812 bytes
SHA-256: 616d29a948383802e09c67f4938f738a31bfac6542ab6e3e59fa2ee14912ee93
font_01_sfnt_off0000faac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAC 17260 bytes
SHA-256: 1fe99169d6d69a4569d479ce599c9a98dd7ec8db3b8996d6c41daf3d881b4ac0
font_02_sfnt_off00012784.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12784 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1