Malicious PDF — malware analysis report

Static analysis result for SHA-256 d163d55242e20296…

MALICIOUS

PDF

70.0 KB Created: 2021-09-15 10:15:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5a3a908919a65a7779addfc4b8c97a05 SHA-1: a27a39db4cc017928dc696642a81477fa8a93889 SHA-256: d163d55242e20296b1a6107d58a15835ca7567d2e6c47c8c0b11137bec1296e3
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://africareview.in/userfiles/file/xapadegalusepekejuwo.pdf In PDF document text
    • http://96rangjai.com/userfiles/file/23061017390.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/24618484372.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16136b3547113d---24541192951.pdfIn PDF document text
    • http://kondicionery-noginsk.ru/upload_picture/file/fefinagivapudidosipa.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614129c814c05---pagozoge.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/fanixeres.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/52849097241.pdfIn PDF document text
    • http://giadinhmedia.com/uploads/files/regolifiloseraxovatagot.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/dugesejixiv.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/noxelavarokab.pdfIn PDF document text
    • https://123natura.com/stockages/files/zojaxotibalib.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614137a227d8c---lupexuluxovizidisokitaw.pdfIn PDF document text
    • http://biznesfishki.ru/files/userfiles/files/71189092797.pdfIn PDF document text
    • http://bayernglobal.de/userVZ/file/wafediz.pdfIn PDF document text
    • https://www.institutvzdelavani.cz/files/10323188395.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/496e08bpn10c6oj4gorpkt2m4q/vufunamadu.pdfIn PDF document text
    • http://byecook.com/ckupload/files/55229838013.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/52826574578.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/cna2u3572jmvqaimmcgnnrsm5v/bebigolawig.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/daxowezemugadelufeledi.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/82740753117.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/59991667160.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=set+android_home+ubuntuPDF 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_off0000b262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB262 15620 bytes
SHA-256: 8a3407f28026c074c8e74203c77647c1ce3fd136744bfa08a3d89c316f64dce3
font_01_sfnt_off0000da59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA59 10648 bytes
SHA-256: 769d243dd747b98c16deb0e55d4086f4934656903efd95a665228d5b30b3ef0a
font_02_sfnt_off0000f288.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF288 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1