Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d8a445724f92add…

MALICIOUS

PDF

84.0 KB Created: 2021-09-14 07:09:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8885b4cda3a963ccd75962a845aa50a2 SHA-1: a52d48abce47d575667fa4881866dcf7a7854e1d SHA-256: 6d8a445724f92add615d6ecc0d380c8f560300d4d02ff0fced7885c276c0ac16
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Multiple external URIs are present, including links to compromised WordPress uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is unreadable due to encoding, but the heuristics strongly point to a malicious intent of redirecting users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://infrive.ru/uplcv?utm_term=download+fake+text+message+apk PDF link annotation
    • https://windsbs.biz/files/file/migimokavozipubexev.pdfIn PDF document text
    • http://infinity8talents.com/userfiles/file/36149173160.pdfIn PDF document text
    • http://guss-ex.de/uploads/fck/file/8785689256.pdfIn PDF document text
    • http://bordahusfeldolgozo.hu/editor_up/wanesolaganimotovom.pdfIn PDF document text
    • https://peusch.lu/userfiles/files/92970386424.pdfIn PDF document text
    • http://letdentalab.com/img/files/49812135047.pdfIn PDF document text
    • https://rmp-familienanzeigen.de/cms/files/vubopozadosuwogaka.pdfIn PDF document text
    • http://kanomax-nsk.ru/images/tolasidakajebixudukoji.pdfIn PDF document text
    • https://speculatio.in/ci/userfiles/files/14344771377.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/zemoneluvitororasu.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/a0c519736975ad8b9bf1ba2060fce8bc/befeka.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff5b79ece9---lasikogi.pdfIn PDF document text
    • https://collinite.pl/userfiles/file/92662558865.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/5299967811.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///tigiputofebutipokejuvoxu.pdfIn PDF document text
    • http://ranch.pl/files/file/37732524296.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/jorodituvewi.pdfIn PDF document text
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/34138791464.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/15241159659.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/luwavafasojevovuzowov.pdfIn PDF document text
    • http://mellorymotors.ru/admin/ckfinder/userfiles/files/96989483540.pdfIn PDF document text
    • http://shanghaicruiseparty.com/uploads/file/95404494269.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/viximikabobakuseroxorav.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/nizijiremir.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/68651db7f5fc5ba0e7157e2c5c1c7bd4/43894768468.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_off0000e1bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1BB 18160 bytes
SHA-256: cc487e84a154fd44d298d0383ca757c85d0227e463cb16013f196b86e02f989f
font_01_sfnt_off000110a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128BE 10932 bytes
SHA-256: ae875c7b9ef587410fda4105875b07ca8466c66a55dc7b51341d3787d40e44c2