Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e436c32f9273cfe…

MALICIOUS

PDF

70.5 KB Created: 2021-09-26 10:03:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6a5c9dee88a86e078d7a982d896553d5 SHA-1: e942271849eb8e04e1d1d187e0599c194bd6ba0e SHA-256: 8e436c32f9273cfec18e45f41ca4a24ca3fed4a8ce257aaffb0a596615e9198b
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting. The ML classifier strongly indicated maliciousness, and the presence of link farms suggests an attempt to manipulate search engine results or redirect users to malicious sites. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific user-facing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • 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://osstemcardiotec.com/files/fckeditor/file/1394495737614da5bedaa0f.pdf In PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/logetomubefe.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/22637115033.pdfIn PDF document text
    • http://praxis-greve-polley.de/web/editor/files/todexigekemutirazepinuxef.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1614fac48c372d---roridiwaxituniz.pdfIn PDF document text
    • http://eko-uklid.com/files/file/99192562624.pdfIn PDF document text
    • https://vokalensemble-vocembalo.ch/userfiles/file/14228431766.pdfIn PDF document text
    • https://dildendilecevirievi.com/upload/ckfinder/files/xubafegijemit.pdfIn PDF document text
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/79913428297.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/kaladedowupirodoxed.pdfIn PDF document text
    • http://branonperformance.com/ckfinder/userfiles/files/jejogosazipudapukogi.pdfIn PDF document text
    • https://chataigne-cevennes.fr/imgs/files/78080434926.pdfIn PDF document text
    • https://protum.se/file/48594838624.pdfIn PDF document text
    • https://hchoanglong.vn/userfiles/file/92117426980.pdfIn PDF document text
    • http://ctcinsulator.com/uploads/file/gefoxawexotumopife.pdfIn PDF document text
    • http://numismatika-nbkpdy.cz/userfiles/file/xiniriginuruji.pdfIn PDF document text
    • https://gulamanis.com/contents/files/dojevewog.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/47126228010.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/26a70283e55fb3929b2481e27429c7cc/milak.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161398e52643e0---gotufuzu.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/rojolebaxidozokarumab.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/fitefokazinemebikurefew.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130db399f42b---wimokijavunanetema.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=galaxy+m32+screen+sizePDF 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_off0000b24c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB24C 16068 bytes
SHA-256: 01f5bd162abf24377de2bd2abd78e25b9a0438e45476d31f4da20614c0373c28
font_01_sfnt_off0000db21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF338 10780 bytes
SHA-256: cef54535edf8cad4c45aaa5fcdbbdb90a46476681e93cdb235d0b80ac06fafdd