Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9cb3104df071c70…

MALICIOUS

PDF

74.3 KB Created: 2021-06-12 23:58:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: d3e104618e0ba7bac31754155abaef62 SHA-1: 906c8c59a8884774d3bdd0d947992154e8a6acc0 SHA-256: d9cb3104df071c70a544e372abedfd3775e7890f7e09f8b48d6454bf2d787d0e
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://nomylo.ru/uplcv?utm_term=esl+practice+conversations PDF link annotation
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ced73f3326---45564321286.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/gixoboximemuroranasoj.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608235629393f---winodekaxefupotatezuf.pdfIn PDF document text
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/44857199319.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/36ca40ebdcc9722f2640803882112238/zobad.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3cd86d9c3---50894692010.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/f559958741daacb6cc186829d3dceac9/zupakajutulebilixozexaj.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/92466077638.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/vf8fe763hpd1ej7umns3bqmgi5/jevutatob.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bce8817b20c---rasumusajowobukon.pdfIn PDF document text
    • http://sola-brothers.com/userfiles/file/kinakipamajazub.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/b33226c2763f6e1bb65c52050f0a5d96/pudemeritoruf.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/9dh61ic68qhjc6ufpl2ong20vm/61335173274.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/velowipoluxevo.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file/%5C/2021050115570869.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/7e773fc25997d725e25e88ac462c0162/72914807793.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcb7cc9e8e---pupiwibedexupi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE567 4944 bytes
SHA-256: 9ea91ac94bf5f62775c878bd284d1c7d8d6fc9bca84d2538472efbe9b292fbc4
font_01_sfnt_off0000f650.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF650 11280 bytes
SHA-256: 1ec68db838f29fba762c3c8f024468c232a00a5a31a42d916ccc406defee4482