Malicious PDF — malware analysis report

Static analysis result for SHA-256 872d8872ea4d7772…

MALICIOUS

PDF

86.6 KB Created: 2021-09-14 09:14:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 83e29f022c08e21841d9479cd8b6fe88 SHA-1: f6639af1083c5b30ff5c8cd320d2150cd8c5b852 SHA-256: 872d8872ea4d777218769ddd2e2c32c67edfc8c159c35f3bc66196cecac903a9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and is described as a link farm on disposable hosting, suggesting it's designed to redirect users to potentially harmful websites. The presence of embedded URLs and the PDF structure point towards a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://infrive.ru/uplcv?utm_term=duplicate+files+android PDF link annotation
    • http://signatureshreyas.in/userfiles/file/64528881384.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/67706976230.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/95750289752.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/1968892149.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/tituramimosokiligulis.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/0vdtcn7j3uuts7t570nhh3b475/rosakanevowab.pdfIn PDF document text
    • http://ceresasrl.it/userfiles/files/98684525480.pdfIn PDF document text
    • http://detskaoptika.cz/ckfinder/userfiles/files/79750726700.pdfIn PDF document text
    • http://net-marketing.hu/images/files/jetumotevukogok.pdfIn PDF document text
    • http://lussoleathertiles.com/test4/EDITOR/example/v2/userfiles/file/20882939619.pdfIn PDF document text
    • http://inspiredindianfoundation.org/uploads/34376164403.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/vilobeleraxegavow.pdfIn PDF document text
    • https://energooptima.hu/upload/File/lutagepegogubidafe.pdfIn PDF document text
    • https://thieumaunao.vn/workspace/develop/uploads/ck_upload/files/migel.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/nolibonosasisub.pdfIn PDF document text
    • https://fancybox.pamlskovnik.cz/ckfinder/userfiles/files/sevewefojewimozife.pdfIn PDF document text
    • https://homecareangels.ca/files/files/files/29518055650.pdfIn PDF document text
    • http://mama-care.com/UserFiles/file/fabinirizak.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f05c4c7850---ravitutefad.pdfIn PDF document text
    • http://edmo-cars.nl/images/file/bojazemo.pdfIn PDF document text
    • https://itexpertdog.com/upload/files/maluluvowonesenekadox.pdfIn PDF document text
    • http://progettarecasa.com/userfiles/files/98020392523.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/57360429113.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/30144687939.pdfIn 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://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_off0000ec91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC91 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A8 10712 bytes
SHA-256: a2d11e76ff4ceebd34d6e54882a0a29fa349f8f5164aec0c3c3d8204c0bacd93
font_02_sfnt_off00011d64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D64 18336 bytes
SHA-256: bf95780292ebd83846603e3088046112f41df90f9ab671add4737dbe0db24ab0