Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ee8d74bd1eb9ec5…

MALICIOUS

PDF

84.8 KB Created: 2021-09-22 17:32:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c3e760dbd5972d3c37d684027e736e57 SHA-1: 2ef8951023645ae3cdb3d513cdfbe6c9a5a4d561 SHA-256: 8ee8d74bd1eb9ec50a7cab3cd049b423fec4b87f0dc4b5f829c83a257018ed6e
156 Risk Score

Malware Insights

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

The sample was identified as malicious by a ML classifier and ClamAV, flagging it as a phishing trojan. Heuristics indicate the PDF functions as a link farm, hosting numerous links to other PDF files on potentially compromised or disposable domains. The embedded URLs and the nature of the link farm suggest an attempt to direct users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://bokaichenyu.com/upload/files/vujekefokejadagerewop.pdf In PDF document text
    • http://rhondachem.com/d/files/14487264847.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021092220460973499.pdfIn PDF document text
    • https://www.rosebankprimary.co.za/inc/ckfinder/userfiles/files/jijogumazosilipudibas.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba8f78cdfe.pdfIn PDF document text
    • https://jamisonfurnace.ca/userfiles/files/71765083193.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/66667787950.pdfIn PDF document text
    • https://livres-arts.com/ckfinder/userfiles/files/26300868514.pdfIn PDF document text
    • http://bdsductri.com/upload/files/60165524167.pdfIn PDF document text
    • http://bifruit.mk/ckfinder/userfiles/files/45990252617.pdfIn PDF document text
    • https://horizontire.com/userfiles/file/mifixesog.pdfIn PDF document text
    • http://yourmoneyyourbank.com/uploads/File/newokuvosusej.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/afcdcd50d8fdd29ea019cc65e3016a13/tamuwumivatosoxuzu.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/fomejojegosut.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16142ac165a750---27475805604.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/zurefow.pdfIn PDF document text
    • http://privateeducation.sg/verzsape/demo/upload/admin/files/999353195.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614447d46bde6---91926302566.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cac1c2fa6b---57964855089.pdfIn PDF document text
    • https://inprovitpuertorico.com/ckfinder/userfiles/files/nesujeja.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/xuzojukidebatawat.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161430d53d1b4e---pasujoji.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/mozebazatoxomi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=track+gpx+androidPDF 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_off0000eb15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001032c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1032C 10404 bytes
SHA-256: 2410905d6fca2a80dcc5b5ed2668e8364ff5ac7077bb4df6744f5884f9b1582d
font_02_sfnt_off00011a98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A98 16896 bytes
SHA-256: 7ebe1b0cbc5798758124a50d688436d439ece9e394aa7bf569efdd69689681d4