Malicious PDF — malware analysis report

Static analysis result for SHA-256 903107ea6b76094d…

MALICIOUS

PDF

75.4 KB Created: 2021-09-21 02:50:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5ea3380e35c922704cc634b92bdce121 SHA-1: aac1c27f53d82136536a9c465181f2fea571e522 SHA-256: 903107ea6b76094d76834c05b22259852fa2c0efbacd5fb422f7eed4e24be25e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lead users to malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or malware distribution intent. The presence of multiple external URIs and link farms points towards a phishing or initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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 http://tznjl.com/userfiles/files/pomemuwozoj.pdf In PDF document text
    • http://sinching.com/uploadpic/files/202109031450469258.pdfIn PDF document text
    • http://capriololaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/daronifimufowaxakajakig.pdfIn PDF document text
    • http://www.adarshvidhyasankul.org/userfilesfile/1978221887.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/91555752812.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614145eb3c64b---58199326219.pdfIn PDF document text
    • http://placc.info/up_image/sewuxafojifuniletifo.pdfIn PDF document text
    • http://hkalc.com/userfiles/nadute.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/82947589672.pdfIn PDF document text
    • http://fge-service.com/userfiles/file/27054635131.pdfIn PDF document text
    • http://ljsmelt.com/upload/files/17514260067.pdfIn PDF document text
    • https://martas.vodrsport.cz/uploads/files/vavopoperuzoviveliwopeje.pdfIn PDF document text
    • https://nabsangram.com/userfiles/file/65098662551.pdfIn PDF document text
    • https://creativenursery.net/home/creative/public_html/ckfinder/userfiles/files/nemiwipapagesikux.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/69994637158.pdfIn PDF document text
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/10343787467.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161452ae6177fb---4624827115.pdfIn PDF document text
    • https://trvstore.com/userfiles/file/sebepo.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/161341aa179f68---45716069777.pdfIn PDF document text
    • http://dongbanja.com/userData/ebizro_board/file/34155609894.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/jaboridivo.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/6120870097.pdfIn PDF document text
    • http://carbonelite.ru/file/fajeduluv.pdfIn PDF document text
    • http://eksternest.be/images/file/rifitijanirotikiwok.pdfIn PDF document text
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/jirebunimipijag.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/vurikuxegasijuju.pdfIn PDF document text
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/duguk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=online+pdf+to+excel+convert+freePDF 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_off0000be5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE5D 10476 bytes
SHA-256: 96472d4312fbf274f8309a8e2acad212be6ff59633e45530e388c4474df308fa
font_01_sfnt_off0000d645.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD645 19112 bytes
SHA-256: ad173ab0710abfaa6a6b7ecd4d8c9c4c6f44a7b121b41dffee46353212ff99df
font_02_sfnt_off000107ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1