Malicious PDF — malware analysis report

Static analysis result for SHA-256 a16223a993156b27…

MALICIOUS

PDF

82.1 KB Created: 2021-09-02 23:35:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 43d5cd74849e70840eb1fb5d6c739e1e SHA-1: 2a4dab9500e442b3112c720f112c5cc96b7434c2 SHA-256: a16223a993156b27e1666d33673a6045e98624bd6617ee34dae0594a8618553a
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to compromised WordPress upload directories and disposable hosting domains, indicating a phishing or redirection scheme. ClamAV detected this file as 'Pdf.Phishing.Trojan', and the ML classifier also flagged it as malicious. The primary attack pattern involves directing users to external, potentially malicious content through a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://portalcom-b2b.es/img/user///file/_0936008001627095155.pdf In PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983dc89c892---tikofamejofodefitajob.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/62f750c9b9dadb322817d6dd3f7e8841/zusoxifixiguve.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7d55ecd2c---96419130010.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/h0nscmqat161ps7tufueem3mci/sawadap.pdfIn PDF document text
    • http://wonderful-foods.net/userfiles/file/6310977161.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160c974491b0b2---ronenewonuzanisuzoruziged.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/cf7544e3ec324d899202653467fa9d00/pamapopefonubutodedenegos.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/10aaa4313e96abb2e84f6b9746e1b0b5/pupibeveguvubunimodewu.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/wulapiparinexuvesisatofi.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/1p75bk53rrojeqqlnv590lujp2/60630282431.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/turedekemesavusidinebu.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///92012037708.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/9853ee7d8d8ccf09d7b486902cf5cc1a/64040614345.pdfIn PDF document text
    • http://quaretti.it/userfiles/files/65889921783.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/bb0487cef222abc13b49715ec6504e38/22621124909.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/e05893e09621e10cba1542bba42ffbe4/tabidirexuzoxivolaj.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f27023bbfc---13000776858.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/mulutu.pdfIn PDF document text
    • http://ansonseatery.com/uploads/files/29414295147.pdfIn PDF document text
    • http://guilfordvikingsclassof81.com/clients/4/47/479b0a304b4cdce99dfe3eda73a59016/File/93971150871.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/merik.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609d6e590f9df---62567039870.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/24589792867.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fb6804078ee---tonizo.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160a007fae9002---vepewapibuzopu.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609450466638d---vesemugiguzerajemik.pdfIn PDF document text
    • http://guanzhuli.com/userfiles/file/63913935607.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=lirik+sholawat+nariyah+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_off0000d426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD426 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC3D 10712 bytes
SHA-256: ba5b0d6d4fd2fbefd1243e5ed828356c76acddf65eefddbe46828cd21837e02e
font_02_sfnt_off000104d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104D7 20904 bytes
SHA-256: a3db26788295a698e37762e324328b018a2ce1472bf921d3e3c285ed8cca050b