Malicious PDF — malware analysis report

Static analysis result for SHA-256 6fe51c5e910c1436…

MALICIOUS

PDF

93.4 KB Created: 2021-07-06 22:26:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 28633b7775e274e466134efb721aceb1 SHA-1: 846bdbfea6b8462f41b474c1a4f19a9fbe962e25 SHA-256: 6fe51c5e910c1436cf8a0106ae3b445862fadcccba5bf0599d5ee82fcf6825d0
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting it functions as a link farm. The primary goal appears to be directing users to potentially harmful external websites, as evidenced by the PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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 https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/3a5ea33f492bff8ccc397575c1e08351/memubutemalemig.pdf In PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/16086ff8b7693b---xilidovajufaxasarowefa.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/jolalotivodolof.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/29a0ec9u2forqko101612s40t3/dinan.pdfIn PDF document text
    • https://aquatim.ro/uploads/files/12890699049.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/6r2evggrq5ppjgpnk6t641j6ts/4161697061.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072ad4f1042b---pezobenozik.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/15946329601.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b38ee19b4---9023759331.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/e19b97116899d6de1b46ea6009cb3c1e/pitobimobutefu.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2b6f7072e---bupifumexizobowowizajop.pdfIn PDF document text
    • http://bigandtallking.com/userfiles/file/juletakotetu.pdfIn PDF document text
    • http://hasanmasat.com/ckfinder/userfiles/files/davilisepodote.pdfIn PDF document text
    • https://mamo-tato.ro/userfiles/file/46883534618.pdfIn PDF document text
    • http://technocom.pl/editor/file/dojevesubibofatomaniluw.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788f5336450---wizodevuxaruzonebevisok.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/17014684054.pdfIn PDF document text
    • http://ipsgroupjjn.org/userfiles/file/dekosetasudakodok.pdfIn PDF document text
    • http://tuhocxuatnhapkhau.com/uploads/ckfinder/files/82426968013.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/26956548184.pdfIn PDF document text
    • http://kcobafl.org/ckfinder/userfiles/files/titunurozedu.pdfIn PDF document text
    • https://arhometutor.com/userfiles/file/dubutobixunakuxonedi.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160a710049a5b4---delosesozapeniladugujaza.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/0e8f6c75fe34b3c91648982af02b24f9/velonagixijudodix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=synonym+to+role+modelPDF 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_off00010bee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BEE 10176 bytes
SHA-256: bebb16d18a19ca826793a7f61bf94d0ba0bbb520688391cf22c11b7a7f0e35e9
font_01_sfnt_off000122b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122B4 17572 bytes
SHA-256: 65d836ee1230498ed4c3f9eca836f6f4c26bc7146e00a31e7f35c21169063efe
font_02_sfnt_off00015071.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15071 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1