Malicious PDF — malware analysis report

Static analysis result for SHA-256 da832b50fbcac4d8…

MALICIOUS

PDF

83.1 KB Created: 2021-09-13 01:22:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: db3a67e78f0bf8d2cad202706803cd57 SHA-1: 963a160400fa10a2bc8e253a0e27c787b6722d02 SHA-256: da832b50fbcac4d8aad66d89a4350655ee11ec663cb4a57b3a350032e17572bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS uploads or disposable hosting. While no scripts were explicitly extracted, the nature of link farms in PDFs often involves JavaScript to facilitate redirection, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://sochisushi.nl/survey/userfiles/files/22099674014.pdf In PDF document text
    • http://www.ambatownship.com/ckfinder/userfiles/files/mutebow.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/ruseririxubolakam.pdfIn PDF document text
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/jifedefoxafozisovevesu.pdfIn PDF document text
    • http://pierrevillers.fr/mairie_files/file/58214231705.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/3211224739.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/xopuvokut.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/dofuzewu.pdfIn PDF document text
    • https://emotionalgift.youngzonejewelry.com/ckfinder/userfiles/files/14399442567.pdfIn PDF document text
    • http://lamekatus.com/uploads/ckeditor/files/86825710868.pdfIn PDF document text
    • http://sirindhorn.net/upload/File/39111069063.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/gituda.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f466344c74---27720855027.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/sifebifolugose.pdfIn PDF document text
    • https://basisnomor.com/contents/files/73173293149.pdfIn PDF document text
    • http://1-cities.com/blog_images/blog_/file/9712633259.pdfIn PDF document text
    • http://aeon-dev.com/uploads/files/202109031219541503.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/59369471747.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/69fbqprjinstb8b7t01r9sviqf/63822064811.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/kisofekor.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/cc442d16173e5cd52a5dfeb635671f76/jijovedasixeg.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/lujetakoj.pdfIn PDF document text
    • http://lavalnerina.it/userfiles/file/25620145903.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=felix+the+cat+game+for+androidPDF 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_off0000e2a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2A0 10836 bytes
SHA-256: 713c1263cdd3605db92bcad123811056bbe588388c4ae1af4ea1494f6d93e751
font_01_sfnt_off0000fb36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB36 16972 bytes
SHA-256: f566284ad458f6291d0b5f096a3ebda1520c908a5f98ece5659d2e5e5e321818
font_02_sfnt_off000126bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1