Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a4d4464043d475a…

MALICIOUS

PDF

68.9 KB Created: 2021-09-16 12:47:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 90575eba11127175ee90090442690c3d SHA-1: 939378bc1ad2d738813ebb0591bc7ff0de389d78 SHA-256: 3a4d4464043d475a362d68cf0e7282ff0267445089e340b03b66a67a598e67d0
156 Risk Score

Malware Insights

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

The file is a PDF containing a link farm, with multiple URLs pointing to PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of numerous links to external PDFs suggests an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zhouzhuanx.com/v15/Upload/file/20219122314245257.pdf In PDF document text
    • https://matharu.ae/userfiles/file/fevoribifinozozofekupuz.pdfIn PDF document text
    • https://bunianco.com/other_files/File/24631868882.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/16887288643.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613e94fd2a315---11044538867.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1614192ef3e6ce---lugutomufexukefo.pdfIn PDF document text
    • http://chongros.com/userData/board/file/7021656276.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/piwajubamup.pdfIn PDF document text
    • http://www.biosafety.biz/ckfinder/userfiles/files/solidebusutagukefurukusi.pdfIn PDF document text
    • http://redeyeldn.com/userfiles/file/84783708130.pdfIn PDF document text
    • http://fabrikando.com/cmsimple/images/file/favomojevezibitifeme.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/figafin.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c479d2b1b---dukovarajifazawenijugoro.pdfIn PDF document text
    • http://theorientgarden.iorderfoods.com/uploads/files/mevupibubafavokewajoni.pdfIn PDF document text
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/begozipevirunusanupi.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/wodaji.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/jixamemuzikigisolotiviw.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/seniwuloxapis.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/71ebfc2821bf68abd85542a9c1d05d43/mopaj.pdfIn PDF document text
    • https://ud-hobby.com/images/Upload/file/jemisufijesuruvep.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/djhmf6b1m9qbrejrdupca1hopg/76840879848.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/jukofabotofatizuwuxona.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613e322057734---nugiziso.pdfIn PDF document text
    • http://mega.kz/media/upload/files/roxotofavaxiwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=need+for+speed+payback+apk+modPDF 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_off0000b0ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0CA 10764 bytes
SHA-256: db9df605b56fcd310900977333c40ad134a91901c73aa17e692a43f22e00f639
font_01_sfnt_off0000c96b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC96B 14580 bytes
SHA-256: e288d2ee1b6705a72d9def9a936866154abb6380b05387b815d17831aa3891be
font_02_sfnt_off0000ee1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1