Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b779c4d8d68ab76…

MALICIOUS

PDF

97.3 KB Created: 2021-10-04 23:32:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 12cb7cdd8ac430ef3bca3d1603727fae SHA-1: 3284ba5e0282a69cfbc556df31e30bc840fcc93d SHA-256: 4b779c4d8d68ab7618b58f3585e85255db962dc0772a2b9f3ee503465c30f7b9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains a link farm pointing to multiple domains, some of which are hosted on compromised CMS upload storage, suggesting an attempt to distribute malicious content or phish users. Embedded JavaScript streams are also present, which could be used to further obfuscate the malicious intent or redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://battlegrouponline.com/app/webroot/js/ckfinder/userfiles/files/xalenulutibuta.pdf In PDF document text
    • https://fsbulletsandbrass.com/userfiles/files/38722496122.pdfIn PDF document text
    • https://almavilag.hu/files/files/35882151183.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16135ea166b0bd---febudurofalojedapozufi.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/70132331600.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/98621880001.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/userfiles/file/74790661685.pdfIn PDF document text
    • http://www.serenissimaservizi.com/files/60020234814.pdfIn PDF document text
    • https://valeaflorilor.ro/img/uploads/file/4233031812.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/gewovenedivitilasopi.pdfIn PDF document text
    • https://xn--b8qxb801j.tw/upload/files/33447184265.pdfIn PDF document text
    • https://fiscalonline.eu/app/webroot/files/userfiles/files/dujonorinomigonil.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/78046098699.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/gunipabegaxuji.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16158a4daefcd4---28250850277.pdfIn PDF document text
    • https://gbp.dropship-online.com/userfiles/files/zerirulegotapisiforafed.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/dibanofuzuderiveri.pdfIn PDF document text
    • http://htbestcomputer.com/media/ftp/file/66992609305.pdfIn PDF document text
    • https://viboot.traigiongthuha.com/ckfinder/userfiles/files/sujavufavovotisozavan.pdfIn PDF document text
    • https://vgcanada.com/userfiles/file/titakepekurawojenaxu.pdfIn PDF document text
    • http://greenmodels.ru/uploads/files/55663626376.pdfIn PDF document text
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/43310314008.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/d6adc63b6f3869c1c725d88dfd86cc7c/67181351642.pdfIn PDF document text
    • https://sieuthimayphat.com/ckfinder/userfiles/files/vujipizabidisuruluvi.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/45299085114.pdfIn PDF document text
    • http://kemnhapkhau.com/upload/files/34140892035.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=7+anointings+of+the+holy+spiritPDF 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_off00010ca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA6 22752 bytes
SHA-256: f0eec735a14f6458f3c130a3796218ec9e966e21c33eb34deba79f309fefcc55
font_01_sfnt_off000146b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015ec7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15EC7 10704 bytes
SHA-256: 2faee98cc85ddce30af4cee9704bb95cd8acddb544780a616ca1ccad8ebaee94