Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a35e3e855d887b5…

MALICIOUS

PDF

70.7 KB Created: 2021-06-12 08:44:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: a8fc2363c3b223680f01404786b50041 SHA-1: 4bdd9ab57a3449dafb6362bf5884e291ec8eb7bf SHA-256: 4a35e3e855d887b537fda9b7cda290a5a46327ef43873832ec545287916606fc
104 Risk Score

Malware Insights

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

This PDF is classified as malicious by an ML model and contains numerous links to compromised websites, likely for SEO poisoning to lure victims. The document body, though heavily obfuscated, contains text related to downloading PDFs and software, suggesting a phishing or scam attempt. The presence of multiple external URIs and a visual download button further supports this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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://catamma.ru/uplcv?utm_term=download+pdf+office+2007 PDF link annotation
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c26cb3e51df---81451917679.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/nivepizasinukokexese.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/16077fb0772b0a---bujinafesumivalawer.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608576ca1c198---satotek.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/or7hg3c23tb7rhbsvb5l0opq25/67303191226.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/c7952d61dc6afb6ee754aea3d80082d9/kejufefarawelebexuwajazu.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609474ef19c2d---kumigad.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b78b7d61f4---92817502416.pdfIn PDF document text
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16084b355e7474---24065715000.pdfIn PDF document text
    • http://mjsolankifoundation.com/fck/imagesfile/lufulod.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec97e53d7a---35853128787.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/46386417601.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/3c23376dacbc7cfd7020e737069adfde/66974267481.pdfIn PDF document text
    • https://fallsplat.se/file/99551835917.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b9ce788188c---jupugusogogosumogomotak.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_off0000d8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EC 5320 bytes
SHA-256: b6def051785c7a3b01b50eda8dd688a8959bca80d820e475a9c3834a3474fd98
font_01_sfnt_off0000eb40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB40 11112 bytes
SHA-256: f7f5e06950554678974e40a0fc3cd18f312fb290a178c0d38102ac409d57bb03