Malicious PDF — malware analysis report

Static analysis result for SHA-256 4174835d7329c193…

MALICIOUS

PDF

183.8 KB Created: 2021-08-04 02:37:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: f69c136f943bd8d158a857e6d340b9f7 SHA-1: c7604a3095b1ee10af9efad15ab895f2001c703f SHA-256: 4174835d7329c1932df667e737d39d4925895a9c6956fef85f673fbbd5feb636
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. The PDF also contains numerous external URIs, many of which point to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9708

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 https://retake.dk/ckfinder/userfiles/files/48177631596.pdf In PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/b4676516a0c5a851a6503eb8dc17dbb2/73456833095.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/72144989378.pdfIn PDF document text
    • http://daieimotors.com/js/upload/files/74302224263.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094396fdb5be---lakikuzesavamuzoxulilipuv.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/293887b802945d97175260a9b7c0eff7/saluzolomejejiji.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098540d0a223---rosubigewetamosek.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/0bd2549216601fffc4164e9e05528248/57483158261.pdfIn PDF document text
    • https://hurghadalife.net/userfiles/files/35366079492.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/5vncts3j979p36jic5dnuvhcr9/8560772678.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/jiwitojubapazubotanil.pdfIn PDF document text
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/10984278823.pdfIn PDF document text
    • http://bjsprt.com/uploadfile/file///2021061600570323.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/53864115407.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/78427620295.pdfIn PDF document text
    • http://shsclassof1959.com/clients/a/a7/a7a82b2a6025f7fafce5d77be70bf845/File/buzagi.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e8f8e53ad4c---fagukexaxoxezinebeni.pdfIn PDF document text
    • http://africareview.in/userfiles/file/kuwigid.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/71jtnm16kl2tgongfvoru4tmk7/84438541826.pdfIn PDF document text
    • https://haltia.mx/sii/ckfinder/userfiles/files/zulonesibus.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/62984d4f5c108f5d5f413831504d6f99/deguwawejegaxagob.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/6a9e60b08e206d333b17eec3d0f2cc0a/77439604157.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/meguterop.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/4gp3fseq6koe6eag5jrevhj005/wusizuluvunobifaf.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/s38ntr4l99470ndf46ld60c1i4/88810140422.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e9bd1ffbc---67293945041.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/fd1c6e5b4d29fd9689268e491003f569/tanuwuxukina.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=biochemistry+and+clinical+pathology+d+pharmacy+mcq+pdfPDF 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_off000267fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x267FA 19200 bytes
SHA-256: d8524bb0205e363ac560edd89bc30edccfc4590e098ec0734d3f623714458638
font_01_sfnt_off00029b9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x29B9F 11380 bytes
SHA-256: 98cb12c54a8141044ccc09aa9b2149fab81f0b9ac7a0eda5f51662318d611b83
font_02_sfnt_off0002b5c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2B5C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1