Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c870a705dba7982…

MALICIOUS

PDF

93.6 KB Created: 2021-09-01 14:19:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f033f95680e548940aad3cf853a66609 SHA-1: 73e1a3f87b666e98311f2a3ea15cf7b838e93d98 SHA-256: 8c870a705dba7982bda53611792acdb5a28e0cdb535a3204bc7a8621a8ee0d0d
156 Risk Score

Malware Insights

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

The PDF contains a large number of external URIs, many pointing to compromised CMS uploads or disposable domains, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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 https://archism.ru/uplcv?utm_term=object+of+preposition+list PDF link annotation
    • http://trlgpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/94798693510.pdfIn PDF document text
    • https://vieclamkinhdoanh247.com/upload/files/viwelekigezusuge.pdfIn PDF document text
    • http://df-foundry.net/d/files/36421854167.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a81b3772111---19048142578.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/bojilovimepewegofogebe.pdfIn PDF document text
    • https://artlabjo.com/userfiles/file/fezeluj.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607d706696231---44173910238.pdfIn PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/72281204944.pdfIn PDF document text
    • https://akvaguru.hu/user/file/rurubovapafemekigi.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/13425920658.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/sakumoforufobikin.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/3vn863ugms0mamefjmtfq91cqs/paginalosajov.pdfIn PDF document text
    • https://standardpromotion.com/images/upload/userfiles/files/29735264786.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/vivibet.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/62057985882.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/7fa5a2c66eea9c270e77f924a4377ec5/dumozesevos.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/39246c723a809d20733a1d1ff1287068/sogudoloxep.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/92d71d85f2aa7180ece1525adce19b1f/dadisamuro.pdfIn PDF document text
    • http://tochuchoinghi.org/files/jurerebosewokudizoku.pdfIn PDF document text
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/10840906593.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/xesufakobafixomadarikitap.pdfIn PDF document text
    • http://indianspringhomes.net/userfiles/files/59569693354.pdfIn PDF document text
    • http://sziazsauto.com/uploads/files/56427369745.pdfIn PDF document text
    • http://balade-pierry.fr/userfiles/file/74551133107.pdfIn PDF document text
    • 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_off000106e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011ef4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF4 18988 bytes
SHA-256: 7231bda21eca405eb420d32e3be7c75ddd6988d50c56fefb5c84c0f98757f4f9
font_02_sfnt_off0001500d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1500D 10608 bytes
SHA-256: 1948c66022c315a87af92626ea863aad1342a1a4f28b0021f4208c8ead35102a