Malicious PDF — malware analysis report

Static analysis result for SHA-256 f357ef1d5ce6be3c…

MALICIOUS

PDF

83.1 KB Created: 2021-09-12 05:06:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: acc8cbd44e439e0b03b5d39af5b62a9a SHA-1: 9000b66019692c541b7025bd1d07d7e3b1770c9f SHA-256: f357ef1d5ce6be3cd1ed8a6a2be31fb9f498a28b3470a5a0c75208555a3de596
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of multiple external URIs and the nature of the heuristics indicate a likely attempt to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://faw-asia.com/image/upload/files/5274611538.pdf In PDF document text
    • https://ripedzn.com/app/webroot/files/fckeditor/file/44803771954.pdfIn PDF document text
    • http://china-baby-clothes.com/d/files/23624402537.pdfIn PDF document text
    • http://digitalpolicycouncil.org/imagenes/file/dobemilovevirogi.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/4a07b41e692a2b5dba3072b4ccd53513/71720477694.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/jetakewepavavorogem.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/45870722547.pdfIn PDF document text
    • http://www.accessibilite-salle-eau.com/ckfinder/userfiles/files/31172287733.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137450502c50---11395862648.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/308a8fad63c86e6d308176c04c7df1bc/32962670057.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210912093621.pdfIn PDF document text
    • https://centaur.vri.cz/docs/files/1466586504.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/rovufavaxutatobalurax.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/gowegiga.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/wadudaw.pdfIn PDF document text
    • http://adimhukuk.com/resimler/files/velujebizogidusatewivawo.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/jowozigar.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/jepenelokapuboxerulizegov.pdfIn PDF document text
    • http://thanglong.vn-greenenergy.com/ckfinder/userfiles/files/79495660557.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/gubutawejiwowig.pdfIn PDF document text
    • https://solturism.ro/images/file/10898653849.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/90672619605.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/84906132305.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/tuzediwesevo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=download+launcher+ios+14+premiumPDF 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_off0000e08c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE08C 11000 bytes
SHA-256: ae2f459134131749f7c1fb544dba327b087fcdca59c48f412c6de78d265e91a1
font_01_sfnt_off0000f9ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11211 17364 bytes
SHA-256: e59c686bb470f9502d9233a4205b939ce0de345fd197a6f5ec64b0ab3008f67b