Malicious PDF — malware analysis report

Static analysis result for SHA-256 491a848790cc7dd8…

MALICIOUS

PDF

83.9 KB Created: 2021-09-08 11:19:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7bcc0f15f10c1ec1d3cad57bdab93d68 SHA-1: 7e6c7b3859ff5da8ef969bf098d3fe91b8500d80 SHA-256: 491a848790cc7dd8eab24a46c8f8aea938826958bc041dd26077d9b23fdb1342
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to websites hosted on compromised CMS platforms or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL analysis point to a common tactic of using link farms to obscure the ultimate destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://tasivn.com/upload/ck/files/83141591226.pdf
    • http://longruiglass.com/ckfinder/userfiles/files/20210830_003535.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/7sa0kbdone8ij6gfikt13abj15/62830116735.pdf
    • https://ka-base.no/images_content/file/wuruxanis.pdf
    • https://chief-moving.com/editor_upload/file/38114801119.pdf
    • http://n2nlah.org/UserFiles/file/45844041849.pdf
    • https://likeevent.it/writable/public/userfiles/file/9975357484.pdf
    • http://bluestandard.pl/ckfinder/userfiles/files/83418710795.pdf
    • http://novichiha.ru/pic/file/pesezoxevixofipaliton.pdf
    • https://pacpartner.net/images_client//imagesfile/86293809228.pdf
    • https://sdudyogtechnologies.in/ckfinder/userfiles/files/kagoxexifinopexivefim.pdf
    • http://cariboohose.com/userfiles/file/fojuzoz.pdf
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/duvabasexurew.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/8eb5b46a33dd51adc274e4d0dfac46e1/xudetigu.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100f874161f4---33148757560.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/p92ddmabh0ar63gn6tm9qbh48h/namidodedaxewagixamiwak.pdf
    • http://pronobile.de/catalog/file/kikak.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/4d5l8p8rbb265f18fbr3fc69kl/29759381651.pdf
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d57bf3f058---pigixonurejipasixa.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/8112143165474597b630f4519fbbe25b/62287838701.pdf
    • https://pernambucoimortal.com/imagens/files/zivifi.pdf
    • http://musorcentrum.hu/files/article/file/31193740180.pdf
    • http://anhuizpyy.com/upload_fck/file/2021-4-28/20210428205821327019.pdf
    • http://wohingltd.com/userfiles/wosusoxamivakefekelokuto.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=fiche+m%C3%A9tier+secr%C3%A9taire+comptable+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df07.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF07 16792 bytes
font_01_sfnt_off0000f719.bin
0327a1878fcff8b9cc2f1f643b242a0f9efeddf4b7c8fb6bee3017282d684760
pdf-font-stream PDF embedded font (sfnt) at offset 0xF719 19144 bytes
font_02_sfnt_off00012698.bin
9f20ff6f0f45945c61b6fa37655b85ba87a787799d8c3aa73ce88a74ecbfe0c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12698 11052 bytes