Malicious PDF — malware analysis report

Static analysis result for SHA-256 713c2149391f1f86…

MALICIOUS

PDF

88.5 KB Created: 2021-06-26 00:53:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 3a2167a3ea7ec20a2b2e05c593a7e9cd SHA-1: fc5c04be7285bdbafb9a149c40bb985c5ff04457 SHA-256: 713c2149391f1f860d21a0ed6e92c7d9392cb9b55ad80bfe2245383df897e841
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting, which in turn host other PDF files. This suggests a multi-stage attack where the initial PDF serves to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://gencerenerji.com/resimler/files/zijuzevaw.pdf In PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16097888925ce2---98714983257.pdfIn PDF document text
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/r3ngbham3k3ml6aqpbthjas52u/duwefixik.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/8d0b0b237847c4449155973a1183a9b4/joguduteximol.pdfIn PDF document text
    • http://staropolski.net/Upload/file/fikopabutogavejupe.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717bf192c75---xulup.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/540eb18fe6d1ef1db96e683954214860/17624891741.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/povpe48glfn92e8dsr4rjlggtr/kenezup.pdfIn PDF document text
    • http://wami.cc/data/files/70241940503.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/26226464414.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/bavizijagu.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071cbe902334---63322296375.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/20612095166.pdfIn PDF document text
    • http://kanstm.com/ckupload/files/41446880470.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/15936749490.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abb0f89d38d---vejitoreti.pdfIn PDF document text
    • https://gretajensen.com/ckfinder/userfiles/files/nokafebe.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16078d44f45550---xorolimenu.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/54067590270.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074b8a21dd6b---24942612505.pdfIn PDF document text
    • https://notrepanierbio.ch/userfiles/file/56877919183.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b11540be3ca---ruzobigidiguzene.pdfIn PDF document text
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/4708e8c82fefcb8d2dc740b0c35cacf5/80776436834.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=what+is+the+difference+between+warm+and+cold+blooded+animalsPDF 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_off0000eb76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB76 21124 bytes
SHA-256: fd1df4cc2b8eedaf20495a9f82f71ab9b8f40ec3c233bbf1040bf3a44ee8eef1
font_01_sfnt_off000122a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013abb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13ABB 10960 bytes
SHA-256: 6a95f6e0235a5b2ed6cafcf8e490267c46734f6a8e1160d26912c9f0ab806a55