Malicious PDF — malware analysis report

Static analysis result for SHA-256 940d4544b3cd215b…

MALICIOUS

PDF

83.9 KB Created: 2021-07-05 13:14:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: f98e04c85adb004bb42dd58d3df2006c SHA-1: 26270296976dd0edca9f3e8e7e7203e9ebd30be4 SHA-256: 940d4544b3cd215be621f020905c11e337e93025b67c88081a05ff73671add84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and the presence of many external URIs imply it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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://www.bandungmesin.com/file/19238344133.pdf In PDF document text
    • http://www.nomorcantikspesial.com/file/47783314703.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/zewisigudojuwodotitav.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f46591d6d2---zarowekidudot.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c4fb06e589b---81007468588.pdfIn PDF document text
    • http://alexandraharris.com/clients/36054/File/9665346400.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/82436075110.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/tijadiv.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1608adfb2b1ed9---subebiroditegesuwawajiku.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c293612c6e6---jepegubufolaf.pdfIn PDF document text
    • http://dragonera.cn/admin/userfiles/file/7492253839.pdfIn PDF document text
    • http://polkovnik.su/upload/file/liduzeg.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/7908146176.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/ug30kdmik3nvj3h0nrdesj16ad/nawenonu.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/ruicp0s5mf10mvvqsbe7mgeli1/34850910957.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/5826249611.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a310492e305---93254289591.pdfIn PDF document text
    • http://anjilh.com/uploadfile/file///2021043021520066.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae4c0e497a---5363242438.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/89465895254.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b120077575d---zepegom.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/640df5eac8dc3c3a3bce414a5a177ea7/wupazil.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e21cf34a98---32506900564.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/cfde299e624667e70cd0eea1866e40ae/xuxivovizikozapuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=find+the+equation+of+the+perpendicular+bisector+of+the+line+segment+joining+the+pointsPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cbb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB5 16088 bytes
SHA-256: 450eea5fc67953cc3bdc764260aa6f1739571c17331c9588074966c3dbef4c6c
font_01_sfnt_off0000e0e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E6 17200 bytes
SHA-256: abc355f9cc02e8f8d34289b82cb86034d9e4b1c29febf84cbfbff0a616425f73
font_02_sfnt_off00010df8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off0001260f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1260F 11560 bytes
SHA-256: 66dba1aa46981e4ceb7d771863d196e7ed6fd718b06f0997c7c973823dddc9d1