Malicious PDF — malware analysis report

Static analysis result for SHA-256 833b2951cd07dbad…

MALICIOUS

PDF

85.9 KB Created: 2021-09-28 02:23:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 28cd606d693852a87f156bf387d5672b SHA-1: 5d6d10d09e867a4ba21ad88828e0ca46251ab9a7 SHA-256: 833b2951cd07dbada801a74bd35a0414d0e123e7c1824932873b55ed922b8c1f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains a link farm pointing to multiple disposable domains and compromised WordPress sites, suggesting an attempt to lure users to malicious content. Embedded JavaScript was also detected, which could be used to further exploit the user or download additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

Heuristics 7

  • 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.
  • 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://plaschke-partner.com/uploaded/file/73479608808.pdf In PDF document text
    • http://alothongtin.com/upload/FCK/file/rigivatomemirigoguxijobe.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/80229331559.pdfIn PDF document text
    • http://smm-mm.com/uploads/news_file/rareworasebufulilofikuwas.pdfIn PDF document text
    • http://ticketsperiodico.com/galeria/files/pigiju.pdfIn PDF document text
    • http://hyundaiokla.com/uploads/files/49756316610.pdfIn PDF document text
    • http://hstechno.com/userData/ebizro_board/file/basidapuwexi.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/10546023965.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613679e11f24b---76491643703.pdfIn PDF document text
    • http://eatatrudy.com/uploads/files/jujedamedusemalotovuseri.pdfIn PDF document text
    • https://www.ccs-corporation.com/ckfinder/userfiles/files/xosusudevesenoxedaw.pdfIn PDF document text
    • http://cabanagarden.hu/editor_up/pesonetipukefumujod.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614b13a205ff0---75527210647.pdfIn PDF document text
    • https://gangnampools.com/contents/files/19896468714.pdfIn PDF document text
    • http://szentistvanpatika.hu/upload/file/61495690684.pdfIn PDF document text
    • https://andana.us/files/files/98959359118.pdfIn PDF document text
    • http://moto-bike.pl/userfiles/file/61564200696.pdfIn PDF document text
    • http://hiace-yoshikawa.com/js/upload/files/xasekudiduxowalixowelikup.pdfIn PDF document text
    • http://kdwatch.net/upload/files/2021091406075422.pdfIn PDF document text
    • https://yantrasearch.com/ckfinder/userfiles/files/gewezo.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613349364e8fd---xenubifepigavalanogugarap.pdfIn PDF document text
    • http://engcaphone.com/_UploadFile/Images/file/72972040996.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/76502374260.pdfIn PDF document text
    • https://diphong.com/uploads/zizasoninurivejotoxax.pdfIn PDF document text
    • https://hk-delight.com/UploadFiles/file/87649971116.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=redmi+note+10+pro+vs+redmi+note+11+proPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c9ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9EC 21800 bytes
SHA-256: 00d0822504bd5e2c8c614aaa0f385f84e383540af35a557d0b3135f8f7343a9b
font_01_sfnt_off00010304.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10304 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B1B 10632 bytes
SHA-256: ce427785afdfdc549272c38fb9f500ac6cbd2a19e1f9c2bf1e068edd5ba1586a
font_03_sfnt_off0001336e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1336E 16188 bytes
SHA-256: 800554d3d6320da9c8ab21a3ad3d270f40e7a92360d7538c059d647d952d1d34