Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef03cdb8bfe197c2…

MALICIOUS

PDF

70.0 KB Created: 2021-09-24 18:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7f9515adf00eff64bef368a41f5502f7 SHA-1: c3411ccdaecd7b688afcd8bfb15fede936b2a4c7 SHA-256: ef03cdb8bfe197c27ef011604bdd709c6fcdc097260d8d1340506aa7e72854ed
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised websites, likely intended to trick users into downloading further malicious content. The ML classifier strongly indicated maliciousness, and heuristics identified the PDF as a link farm on disposable hosting, with several URLs pointing to compromised CMS uploads. No scripts were extracted, but the overall pattern suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b41acd3981---46708654050.pdf In PDF document text
    • https://clubesolbra.com/uploads/files/loduposevivitagane.pdfIn PDF document text
    • https://costarica4d.com/contents/files/36627809897.pdfIn PDF document text
    • https://amoslodge10.org/ckfinder/userfiles/files/taxuzefufinositemewawu.pdfIn PDF document text
    • http://rehahomecare.com/upload/editor/files/labuba.pdfIn PDF document text
    • https://conrays.ru/f/data/wovulaboz.pdfIn PDF document text
    • http://gajagotour.com/UserFiles/file/63772776351.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/161480177a3b78---sodakagadovexudodekefu.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/5459e6979801d14f8fc83983f4741dd0/juwaf.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/f5653e0d85d07a343e74d909803b91f6/zofalak.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb1caed117---31003782878.pdfIn PDF document text
    • http://www.memoriahistoricamalaga.org/ckfinder/userfiles/files/63840853237.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/55206536627.pdfIn PDF document text
    • http://aisne.proximeo.com/ckfinder/userfiles/files/28767872562.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/4314892259.pdfIn PDF document text
    • http://masterkontroll.hu/ckfinder/userfiles/files/8350919010.pdfIn PDF document text
    • https://pianotuningdarwin.com/userfiles/files/wonalusizimiluzid.pdfIn PDF document text
    • http://nhatngungoisaoxanh.com/upload/files/ligefirokito.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210908195135962.pdfIn PDF document text
    • http://sdtrafficticketlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wufir.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/fibasavew.pdfIn PDF document text
    • http://verkaufs-akademie.com/userfiles/file/86265478361.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/60917078988.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/wuwodofew.pdfIn PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/vijikizexukidavezukuzad.pdfIn PDF document text
    • http://picart-personal.pl/fckupload/upload/file/64676662629.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=akun+google+androidPDF 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_off0000b553.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB553 14944 bytes
SHA-256: 0dc4ec30a0352e861be7dfd2f4eb90018f92e1f95abb8d783002f260e52fbfce
font_01_sfnt_off0000db30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB30 10332 bytes
SHA-256: 8e8db1435fe21ea660da07796615735f7fc146866d0c8b4c096b34842f22effc
font_02_sfnt_off0000f259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF259 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1