Malicious PDF — malware analysis report

Static analysis result for SHA-256 439c91e602dc097a…

MALICIOUS

PDF

85.0 KB Created: 2021-09-02 18:09:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dfbc00ea80972d4657822ad8f059a618 SHA-1: 7df3568483233a3a121382b830f5eda393a6f272 SHA-256: 439c91e602dc097a89c0a0356aa59108560a12d56bdd455de34d74202d630469
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which are identified as link farms on potentially compromised or disposable hosting. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The primary attack pattern involves luring users to click on these links, which likely lead to phishing sites or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://usaoxin.com/userfiles/2021-5/file/82598007662.pdf In PDF document text
    • http://sushiosushi.com/uploads/files/zosikutiz.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16100d14218180---baleselagodukov.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/40691701548.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/b85704e7b83885241719d92276634d4a/suzubozix.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/46414577264.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/bivinil.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/redejizija.pdfIn PDF document text
    • http://pogologistics.com/ckfinder/userfiles/files/sozimor.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/eknvikmictuvsibpgpv18fhok7/27670344426.pdfIn PDF document text
    • https://evermoral.hk/upload/file/1628665383.pdfIn PDF document text
    • http://hvpeds.com/upload/contents/file/41244797297.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/0qv3mfrb08r9l8psv869cfe7ro/jimiwutetajisawulozedenov.pdfIn PDF document text
    • http://dzbnf.com/upload/file///dibemixekubawif.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609aade1d27f7---46583467193.pdfIn PDF document text
    • http://kbchina.de/upload/61742622065.pdfIn PDF document text
    • http://szrealty.net/uploadpic/2021-6/file/2021060308291073499.pdfIn PDF document text
    • http://www.doctor-carpet.com/wp-content/plugins/super-forms/uploads/php/files/egfrsc050ustl20tr8uc5cq755/99954963403.pdfIn PDF document text
    • http://agro-partner.com/Image/files/jusitujemidowuxuj.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/8534cf974cf77139c007df2824621ef8/95218898326.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/pqk4ebbama7f8mgaqb3etgabb6/63891500688.pdfIn PDF document text
    • http://architettobotteonpierpaolostudioabacus.it/userfiles/files/61220008639.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fa118b16773---46673929590.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/036etbvsvpel7hsmo15lgr9pht/kowogetemonisagerujalise.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210627014114_ypc7cd.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=l%26t+switchgear+catalogue+2019+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_off0000e19f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE19F 22492 bytes
SHA-256: 5c0c78bd7b4089454745566eaacfece225e720845ebf496bfe06c31be2173418
font_01_sfnt_off00011cc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC1 9032 bytes
SHA-256: 76eb9bc0876d8992c1a4f469656a194a5051785caf149127922d177b1cdfc18f
font_02_sfnt_off00012f2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1