Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1818ee4f9460a88…

MALICIOUS

PDF

85.7 KB Created: 2021-09-07 02:37:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b887011c0d1876b682562247f7b0d05f SHA-1: 22bb0a17e6779d72e2eefadb8bc694f9b7d0b099 SHA-256: a1818ee4f9460a88f5c3be0cdc5652fef28181bc2e63e3356ebaf2c002b3dc7f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to various websites, many of which are hosted on compromised CMS upload directories. The primary purpose appears to be redirecting users to potentially malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.willmarareachamber.com/ckfinder/userfiles/files/69080111858.pdf In PDF document text
    • http://sdes.in/uploads/69558497945.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081088724ae4---fezetojovakivulaxavu.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/c80a46dd4235c78c1c4e6963f373bc26/putudewarimu.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/50f01d5e47aa369f19bf73b45609cc38/lojuwupijapiwebe.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/gevidamutugotunilavirim.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/wezupobidufirura.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/fe66cf7e1eee7dd3c42b7f083b14de52/didojibabuma.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/nugawibopesaro.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/72f2abf970320494fb40c065c9333686/72427615256.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606de962380b0---18012047535.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/tafewewuzuxavutapev.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a141f34c5ea---wanija.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160c6c274db3b1---suvalodowinetubufibanabuv.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160feda0234a7a---tanuxugevodipasitoruwafo.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/safexoxijefubepepo.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/kezivado.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/9250d832a7ecb5ab048334de0f2bc4e9/84544098070.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/5402977219.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/64384730025.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/22643019819.pdfIn PDF document text
    • http://xn--clinicaquirogavilario-vbc.com/wp-content/plugins/super-forms/uploads/php/files/u27fe43cbrgjmpo0ltmpv5og24/tujugavivujaxezarixupibut.pdfIn PDF document text
    • http://nokianhakkablue.ru/ckfinder/userfiles/files/tujanafajigagozolisuxeb.pdfIn PDF document text
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/1610c95d7db19d---1972353130.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=grade+5+titanium+properties+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_off0000e720.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE720 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ff32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF32 18932 bytes
SHA-256: ee5a52f7494bf2aeeff539e885f1114160a035797f702b4c691c4558ea35e5c2
font_02_sfnt_off00012fe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FE4 10884 bytes
SHA-256: 50fbde2ee57ce6f743e0251d2a2b1c471fa6e2d83bcf123cee89d38330404c43