Malicious PDF — malware analysis report

Static analysis result for SHA-256 0442f9e233b93e3c…

MALICIOUS

PDF

85.8 KB Created: 2021-09-06 13:52:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ae6d744cf60535fab4850ee76a5735f SHA-1: 31cdc7c50c62298afe04c5313e634b8761f99e7b SHA-256: 0442f9e233b93e3c8f0d87e4b77a3fad99580b905802ff85ec82e3e11b14430a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several heuristics indicating that these links point to compromised CMS upload storage and disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to phishing or malware-distributing sites. The document body is heavily obfuscated and does not provide direct clues, but the link farm nature is evident from the heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://rlangkhan.com/upload/userfiles/files/53007279559.pdf
    • http://elcampoeco.org/FCKeditor/file/23935662797.pdf
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/e45o1tigd7cja3hcaolus89v55/4583613350.pdf
    • https://thehouseproduction.net/file/85296313842.pdf
    • http://finproekt-msk.ru/userfiles/file/56602704536.pdf
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/af085f04a63703edeb6ec5ce1396edad/85061631038.pdf
    • http://veganogle.es/uploads/ckfinder/files/wabelexagapukul.pdf
    • https://damiel.eu/userfiles/file/95129898286.pdf
    • http://nenayu.com/filespath/files/20210901063647.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c4e248386a5---22429956454.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/e3acca6aa9ff9bb46cd7f7e0f5b622e2/56693343245.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609272c2d2675---waxazafuxijuwawomuleru.pdf
    • https://rosycaffe.com/file/lipefunusokufipegaweli.pdf
    • http://klimatyzacjaradom.pl/userfiles/file/tizijumufo.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/d5ba27009866940bb70028c712b27c90/wurokov.pdf
    • http://hpworld.hu/data/pic/Image/file/logafana.pdf
    • http://eperon-kochersberg.com/img_db/finemisunavari.pdf
    • http://dreambeauty.kr/upload/fckeditor/file/lapefelesojusavezexu.pdf
    • http://mediedil.eu/userfiles/files/33640349968.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085048b2d698---kufawusa.pdf
    • https://ribaczpeter.hu/files/file/80629309187.pdf
    • http://grupopiscis.com/upload/files/wejulanevi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=autismo+e+inclus%C3%A3o+escolar+pdf
    • 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_off0000e59b.bin
63062a6b3da17d39eb313e4a1f06fae6bb45db487a0112907385da2fe1e40b02
pdf-font-stream PDF embedded font (sfnt) at offset 0xE59B 19472 bytes
font_01_sfnt_off000115f4.bin
d12dc2cdb95bc50fec658928a2666b906bd2fc38cd847872cf1783c1410e59de
pdf-font-stream PDF embedded font (sfnt) at offset 0x115F4 11128 bytes
font_02_sfnt_off00012f86.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F86 16792 bytes