Malicious PDF — malware analysis report

Static analysis result for SHA-256 d55d320b9aeb1e35…

MALICIOUS

PDF

73.6 KB Created: 2021-09-13 08:19:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b7bd9dba8fa03a0a100235fbcfdc6e55 SHA-1: 339c47edf7eee9fc08a40304f8d9ff76d367f749 SHA-256: d55d320b9aeb1e35aa8aa5160188dfe26aa2e6cac4f24e15947caac00d1837ca
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high ML score and ClamAV detection, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's a link farm designed to direct users to various external sites. While no scripts were explicitly extracted, the presence of numerous embedded URLs, many pointing to unknown or suspicious domains, strongly suggests a phishing or scam campaign aiming to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pharmnet.cz/ckfiles/files/files/87734442660.pdf In PDF document text
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/5421263846.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/marefibiwirodowotadot.pdfIn PDF document text
    • https://atavio.ru/files/file/10833063024.pdfIn PDF document text
    • https://hnhaa.com/userfiles/tnejp/files/76383173483.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109032142426202.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/ziligefokogunepibuxokus.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/14844429865.pdfIn PDF document text
    • https://esvigo.com/upload/files/feforidikigerotifetizixew.pdfIn PDF document text
    • http://xn----7sbezcba9a5aggb3j.xn--p1ai/ckfinder/userfiles/files/zakoburubefabib.pdfIn PDF document text
    • http://355353.ru/userfiles/file/lekitagug.pdfIn PDF document text
    • https://brakos.it/file/moborujuzetipunili.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/47506916510.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/79eef704a09255449ce925fccd79570c/34907499573.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d9394fd1b---wokexaketirubabufifos.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/24885556219.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/jukuraxopepojikeme.pdfIn PDF document text
    • https://gangnampools.com/contents/files/biwoniwasenuwezunifez.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/79310881228.pdfIn PDF document text
    • http://compow.net/ckfinder/userfiles/files/2409976459.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/nutixudamofofu.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/47385996351.pdfIn PDF document text
    • http://www.celso.org/download/49141079107.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+do+i+fix+my+keyboard+on+my+phonePDF 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_off0000be4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE4D 10976 bytes
SHA-256: 9208166a8602fc06081b8aedfb0535699aeb6b201b4acf39cd50a24074b07891
font_01_sfnt_off0000d755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD755 16192 bytes
SHA-256: bb0f4a7f31abefa166eba68daaaf5a4412a135ba88b87a5cf16b2872c0749a35
font_02_sfnt_off000100ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1