Malicious PDF — malware analysis report

Static analysis result for SHA-256 36f7875bcee6c8f0…

MALICIOUS

PDF

71.4 KB Created: 2021-09-17 08:30:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: da3731ae72b476a2dac6c65b9135574a SHA-1: 23864f8621f110125a1d1c7850b40f4ad8cbc833 SHA-256: 36f7875bcee6c8f08c88e39c35ea31653c06b123d361c13a9da81b73ef82b706
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by an ML classifier and contains multiple heuristics indicating it is a link farm. The embedded JavaScript stream and numerous URLs, many pointing to compromised CMS uploads, suggest an attempt to redirect users to malicious content. The primary purpose appears to be a phishing or scam lure through a deceptive link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.gc-antey.ru/ckfinder/userfiles/files/78514065440.pdf In PDF document text
    • https://planet-pvc.com/upload/files/61499937868.pdfIn PDF document text
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/vatixupewubedikilazirof.pdfIn PDF document text
    • http://timavoshipsupply.it/userfiles/file/5948057215.pdfIn PDF document text
    • http://tufaghanafc.com/js/ckfinder/userfiles/files/xugagekikiwopivufe.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/4a84695f44025a008966f32844e942b6/24189658670.pdfIn PDF document text
    • http://candemdientu.com/Images_upload/files/51101658359.pdfIn PDF document text
    • http://verkaufs-akademie.com/userfiles/file/fikokuwoleniduruwutodiza.pdfIn PDF document text
    • https://lazerom.pro/media/file/kujalutomogerofalufere.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/56971568512.pdfIn PDF document text
    • http://oppedisanorobertosrl.com/userfiles/files/zukabazazomiwokonunajifut.pdfIn PDF document text
    • https://dennismaloney.ca/upload/editor/file/55509623562.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/25615414187.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/79164870313.pdfIn PDF document text
    • https://aitalk.vn/upload/files/91158828926.pdfIn PDF document text
    • http://holmeslawfirm-iowa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9228902632.pdfIn PDF document text
    • https://incoyun.com/calisma2/files/uploads/78392803475.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/b2738246c3cdf616be75335b10d12442/41951226658.pdfIn PDF document text
    • https://tese.in/ckfinder/userfiles/files/mokezelokujox.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f55dc77c13---87503493521.pdfIn PDF document text
    • https://pellevah.com/upload/files/35232205377.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/48509583041.pdfIn PDF document text
    • https://grafconsulting.pl/Upload/file/jogaxeravazilefamanapesud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=rhythm+games+with+custom+music+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_off0000b718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB718 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2F 11116 bytes
SHA-256: b4ab35b9d59674be3d7c9971c54f254dc1b760f659262ee898db95c52937b09d
font_02_sfnt_off0000e8d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D9 15548 bytes
SHA-256: ca7bca0e2688ce8f2d92d94a656b7939a87902405a09e9273c50bb654b342c24