Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9259ae3123dd625…

MALICIOUS

PDF

74.9 KB Created: 2021-09-01 23:45:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c219d9984465fc6cfb90dfd1deb4af6a SHA-1: ef273e0e74dd9d39d534d3c42d7712ae9b50061b SHA-256: d9259ae3123dd62516e351a077efdc0afaa7ae54e5c4479c87ff045ed76fefa8
156 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to compromised CMS upload directories and disposable hosting domains, suggesting an attempt to lure users to external sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using such domains for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://sochi-polyana.com/ckfinder/userfiles/files/30956429635.pdf In PDF document text
    • http://rungruangsteel.com/public/upload/userfiles/files/winefosapigegexurabana.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/bt4mfv07afmd19csucg9n1ceu1/92963355899.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/osfd64peffkod6111nbeci5g7l/66816197417.pdfIn PDF document text
    • http://stellamaris.cz/userfiles/bidijatogiwome.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/24942477034.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/e59293d0aa575264215d94679397a144/dekunapewezodamozexibovev.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160adf0a5ce7dd---romaraz.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b494125e77b---46277618481.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eed979a8a0---7075150114.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/b26o1j3sg8l39ehkti9n4sj507/rasabebuwesipogoralisure.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca6660465e---34377731095.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ea06419b1---nunufobutikefivemofeb.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609821ec64c26---2621839431.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16092b34366838---39969669145.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/zibogunafigojat.pdfIn PDF document text
    • http://talk200.com/admin/admin/uploadfiles/file/48248164043.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=corporate+law+textbook+pdfPDF 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_off0000c1c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1C9 10580 bytes
SHA-256: 18c355f2f464d8c0084118b2cd58f394488bc3195203b0185cb950271a36cc5f
font_01_sfnt_off0000d9f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f208.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF208 17080 bytes
SHA-256: 1b66373e8278d696958c4fe1c934cae4bdf5ff767acdb7b01638c420b9ff9882