Malicious PDF — malware analysis report

Static analysis result for SHA-256 df51c92988dc6b4f…

MALICIOUS

PDF

82.0 KB Created: 2021-09-08 17:19:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1953705e9e347c288074b7d8762fe140 SHA-1: 813e34d27da2a553ac5097584abc5bb4a3d1b058 SHA-256: df51c92988dc6b4fec0cdea365d8e195ddef11760868eb94e16464a0261f950a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm, with many URLs pointing to potentially compromised websites or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the presence of numerous external links is a strong indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://imailbox.nl/images/uploadedimages/file/dejelobofekutipofe.pdf
    • http://chemonova.com/FCKeditor/file/sinukifa.pdf
    • http://dorrstrechy.cz/UserFiles/File/29812211135.pdf
    • https://nabsangram.com/userfiles/file/raxomozewamagos.pdf
    • http://gonzagafood.com/userfiles/files/62073998115.pdf
    • https://duragloss.pl/userfiles/file/66761387557.pdf
    • http://harlit.com/ckfinder/userfiles/files/20210907_135915.pdf
    • https://tenekedjieva.com/uploads/file/21774852273.pdf
    • http://nanobubblevietnam.com/uploads/userfiles/file/zopisulababitemixagil.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/c7ee7c9666de681c6fd5ea474d5cd0ce/lefabegixatozawozi.pdf
    • http://abc-tel.ru/data/File/20885165101.pdf
    • http://iccj.jp/images/uploads/fckeditor/file/74332581566.pdf
    • https://ijaetis.org/ckfinder/userfiles/files/15187223038.pdf
    • http://asorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/89990946680.pdf
    • http://feldbach-tourismus.at/files/fuzol.pdf
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379ff6f41f3---32743577969.pdf
    • https://uslugiinzynierskie.com/eurostyl/photos/file/xapokejef.pdf
    • http://reanda.com/jingkelun/userfiles/files/20210906092746.pdf
    • https://irish-setter-zucht.info/ckfinder/userfiles/files/41372318092.pdf
    • https://dadesigning.com/daduserfiles/files/65344761181.pdf
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/jipolexokavegazubalabazan.pdf
    • https://kenadong.com/contents/files/26474999206.pdf
    • http://www.springperfect.com/upload/finder/files/17995719263.pdf
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/jixorasupunenaja.pdf
    • https://araprinter.com/ckfinder/userfiles/files/xisugekufesupixigekok.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136d6f7dd97b---88762270524.pdf
    • https://eetravel.net/file/vuromas.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=lowrance+elite+7+hdi+manual+espa%C3%B1ol
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d6c3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C3 16792 bytes
font_01_sfnt_off0000eed5.bin
0021a50e3d5747539eefa8521c3f5bf0c322ee718978567372bad310776bae4d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEED5 17992 bytes
font_02_sfnt_off00011e00.bin
4813d529ce0b0035ea5a7b9f1ba6a36d5ffe19e22fcfdc82db741eb3698aa5fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E00 11176 bytes