Malicious PDF — malware analysis report

Static analysis result for SHA-256 6997ddc90ad68d46…

MALICIOUS

PDF

75.7 KB Created: 2021-09-18 00:01:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1a6aa28530dee2f3d4a6670612a43448 SHA-1: 3284266a058cc3575ee8f495e3f96b99ad5603e6 SHA-256: 6997ddc90ad68d46e4bbf3030b1678265c82c46f649425177007cbdd21ca1431
126 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. It contains numerous embedded URLs pointing to other PDF files hosted on various domains, suggesting a phishing or malware distribution scheme. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic specifically highlights the use of disposable hosting and UTM parameters, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://yacpa.org/yacpafiles/file/fezokirenidoverunu.pdf In PDF document text
    • https://ratosatu.com/contents/files/zitupexawa.pdfIn PDF document text
    • http://wagnerpc.com/userfiles/files/97117871952.pdfIn PDF document text
    • http://mimarkamilozkartal.com/userfiles/files/nitafupawowidoxebifutusor.pdfIn PDF document text
    • https://quangcaowebsite.vn/uploads/files/6776126845.pdfIn PDF document text
    • https://www.icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/9175507220.pdfIn PDF document text
    • http://bighost.vn/uploads/userfiles/file/kesuta.pdfIn PDF document text
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/48556665631.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/nakawufutet.pdfIn PDF document text
    • https://binarbaid.com/public_html/userfiles/file/68199329309.pdfIn PDF document text
    • http://weddingdove.tw/uploads/files/202109120550497171.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613159bbaafe3---93159185672.pdfIn PDF document text
    • http://aloisiquadri.it/userfiles/files/7668557228.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/dozejota.pdfIn PDF document text
    • http://hasadtemizlik.com/upload/file/6005350065.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/13493983905.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202109100635044463.pdfIn PDF document text
    • http://educaholistica.com/resources/img/imagesck/files/xetujamemeko.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/9smjgo6npc9uo5behi8sbpjjv6/vaxuvalotiwikona.pdfIn PDF document text
    • http://e-sheremet.com/img/78675708892.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/duxubamumiwuloxilapa.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/89946637323.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/doxalexubofarisadaruvasej.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/silafugovedobokoxajeve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=hunger+games+rooPDF 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_off0000c624.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC624 10308 bytes
SHA-256: 3169ce740db32e01aebb3c1a0dae4c86425ee4bcd5f5b49a03ef0057f45fa44c
font_01_sfnt_off0000dd4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f55f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55F 17336 bytes
SHA-256: 36f82e5b5dbb43600fcace7d801a5abdb111e7a05c9af6deea66f40b508d6aed