Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f375fc0ec48364e…

MALICIOUS

PDF

88.0 KB Created: 2021-08-21 07:47:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-16
MD5: 9d6431d56d91a2db1220817ece51e1f2 SHA-1: 7ddaee42fc0baea5875ee044b4766ff61b7c9708 SHA-256: 3f375fc0ec48364e38707fcf46755afe5136daa763833d26318a04a57a1cdc12
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites hosting other PDF files. These linked PDFs are likely part of a phishing or malware distribution chain, aiming to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160e0b111bceaf---79065660407.pdf In PDF document text
    • http://booklandbooks.com/userfiles/file/tumeledu.pdfIn PDF document text
    • http://chronocertif.com/userfiles/file/19598803153.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16070cebbe1514---duzotulowibexoduriwexepi.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba6e3c7c3e---26169123056.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/44372862145.pdfIn PDF document text
    • http://familiehollander.nl/images/uploadedimages/file/laxifar.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608f80d5851b5---91683753906.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb058ecb5c7---5678851891.pdfIn PDF document text
    • https://beatmuellerfoto.ch/userfiles/files/70440864351.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/jedilosodatujo.pdfIn PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/79806964349.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9dadd44767---47803348831.pdfIn PDF document text
    • http://pk.mo/userfiles/file/82650900365.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803a25a1891---35590472822.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-4-29/20210429222606961686.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/49091355142.pdfIn PDF document text
    • https://jotelek.hu/files/file/1386349844.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16076c42960649---61951165433.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/5e32a31d991b446425d922bf24e6bf21/kekezuwufun.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/493f92329bc41547000e3209545cec97/pebapanugidanak.pdfIn PDF document text
    • https://www.bistro-e.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef4240eeea---wadobopewexafivinorij.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160cabb2d935ca---pagopidiz.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/7039888625.pdfIn PDF document text
    • http://xn--pr3b03lcdvwu9dpynqkc.com/DATA/file/20210805023746.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+win+cancer+woman+heartPDF 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_off0000f3d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D8 17412 bytes
SHA-256: ccf64f541d4af30c585e138cedd4f51c208eeab733bf26e13099e8657550a79b
font_01_sfnt_off000120b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120B4 10360 bytes
SHA-256: 7bc28a2d342c72f523ff2413fd30ecabd9fc725a62fbbd0576201a363226ca23
font_02_sfnt_off000137eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1