Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec92f2d058967670…

MALICIOUS

PDF

81.0 KB Created: 2021-09-22 18:28:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 2627898f9d0ce6d0fe05f181197f5a1d SHA-1: 953c4dea61549e88baff92ee90c9e85d93bf590f SHA-256: ec92f2d058967670b476b81157a15ee48f86e14da34bf0efc1d2979c124834db
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to various PDF files hosted on potentially compromised websites, suggesting a phishing or malware distribution attempt. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics, along with a high ML score and ClamAV detection, strongly indicates malicious intent. The document body is heavily obfuscated and unreadable, providing no direct textual clues, but the embedded URLs are the primary indicators of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/30896399042.pdf In PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161443a27c289e---28749657986.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/41836663326.pdfIn PDF document text
    • http://lev-steklo.ru/userfiles/file/46127800496.pdfIn PDF document text
    • https://posetili.ru/userfiles/file/tedavo.pdfIn PDF document text
    • https://unaizahic.com/Files/files/65500589740.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/wulekolipadajetefodaja.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/zuwiseragu.pdfIn PDF document text
    • https://congnghiepxd204.vn/upload/files/1844048302.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/90346676214.pdfIn PDF document text
    • https://eastmanllc.net/ckfinder/userfiles/files/warelazu.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/n561o5oj4klj7tgljvh325sk49/wuvexirabuvadoledisisagas.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/53983357906.pdfIn PDF document text
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/36179744868.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/170507038632.pdfIn PDF document text
    • https://marbletreasures.com/uploads/image/files/32617347816.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/72022998403.pdfIn PDF document text
    • https://www.bramfordgc.co.uk/ckfinder/userfiles/files/wumulinoxubiselitir.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/gufagata.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/2e6970aa99dcbc55e797d68560ad00a4/kukebipagefetokopudavije.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/37250480442.pdfIn PDF document text
    • http://hong-tour.com/FileData/ckfinder/files/20210917_E4E291013BCA3F48.pdfIn PDF document text
    • https://bangprice.com/bangprice.com/beta/cms_image/file/fovujifakunamotodo.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/72773437460.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/fuzorabozidej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=fnaf+1+download+windowsPDF 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_off0000dca2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B9 10132 bytes
SHA-256: 296421928e415dd20362fa8e40c9e206777186b1924729cfe5da8dc270d8f000
font_02_sfnt_off00010b79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B79 16712 bytes
SHA-256: 04c9fc8fd1150d6825169d8ca81963cab9d383e287aa2ba47ec3cecfab3af334