Malicious PDF — malware analysis report

Static analysis result for SHA-256 0976fb3146a6900c…

MALICIOUS

PDF

88.3 KB Created: 2021-09-06 19:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0c6554523cdc21d5ee16627909c263f7 SHA-1: f308112a4bc6e0865a6ea3353a079538c0091765 SHA-256: 0976fb3146a6900cec13102d368839311947084c9c099ea0ff38d48200c8ffea
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This suggests a multi-stage attack where the initial PDF serves as a lure to download further malicious content. The ML classifier strongly indicated maliciousness, and the structure points to a common technique for distributing malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 5

  • 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://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160be30ee7958f---99206083563.pdf In PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/nveq7d3h4056qf5c9u8e000bok/4869371427.pdfIn PDF document text
    • http://hotelborgodeipoeti.com/userfiles/files/29140072297.pdfIn PDF document text
    • https://chptravel.ir/data/file/23443362760.pdfIn PDF document text
    • http://eastcoastbiker.de/sites/default/files/file/73768964796.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/71627409766.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/76389417156.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/882fda1c52549a6faaf0cbe9dab18caa/41413615085.pdfIn PDF document text
    • https://otelnamore.com/wp-content/plugins/super-forms/uploads/php/files/30c8b24dc3f4e97501ff1217d0d345b0/87292821153.pdfIn PDF document text
    • https://tonitomov.com/picture/file/rateduxifozigig.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/20480661329.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160983ecc5fbae---disaxakejufanedaxademi.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/22875494740.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/29f6169fcb94a4a1c12239d9056fec66/77930767062.pdfIn PDF document text
    • http://datavincity.com/uploads/ckfinder/files/50198970055.pdfIn PDF document text
    • http://globalcenterhotels.com/bot/ckfinder/uf/files/tudidizutegaki.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160f1abc965f57---3402567157.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607174e274f10---81901793095.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/0ffad2255a710c5a3796e2780b75425e/bizewokanabobudipuguzub.pdfIn PDF document text
    • https://allmassage.net/upload/file/20210621190206.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075fd798b969---duzikin.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16072a1bd2257d---7278365898.pdfIn PDF document text
    • http://abwmountvernon.com/uploads/files/57154567301.pdfIn PDF document text
    • https://demetraproject.eu/ckfinder/userfiles/files/ruzuvosa.pdfIn PDF document text
    • http://digifast.cz/userfiles/mivow.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/lj2l9ttoatke813vdgmpbajdho/nosovuwizimivad.pdfIn PDF document text
    • http://dakhoanhanai.com/images/files/86756823900.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=customer+relationship+management+strategy+pdfPDF 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_off0000f518.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF518 17092 bytes
SHA-256: ac41c78c6ab0ac5d7d6c2ed2a22e8356c0dc87f629f726236ebc5b1eeff456d0
font_01_sfnt_off0001215a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1215A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13971 11192 bytes
SHA-256: 5eb9e081824204b327d6bb9c46c32e4e02bdad3a5f47818cdaab9f2fb770d202