Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3b385dbd3a2fb30…

MALICIOUS

PDF

80.5 KB Created: 2021-09-07 02:33:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 7d84407f6a27f7d867ef4727e08bcfa6 SHA-1: 76dd713008f5bab9f841dc280e4b1f964eec9c49 SHA-256: b3b385dbd3a2fb3056183896d630818531e568a5674b214902b68e3b17e54f7d
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on compromised websites, indicating a link farm likely used for SEO manipulation or to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting and potentially compromised CMS upload storage. No scripts were extracted, but the structure suggests a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 https://hssipm.com/wp-content/plugins/super-forms/uploads/php/files/aedf410fa03c817c12e0874b115da3b4/57896631962.pdf In PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/81037864282.pdfIn PDF document text
    • http://hypotekaprezamestnancov.sk/res/file/36854004988.pdfIn PDF document text
    • https://beatmuellerfoto.ch/userfiles/files/27181357552.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612044122257b---xazeleleb.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16078b87698090---nosososo.pdfIn PDF document text
    • http://maternites-catholiques.org/ressource/site-image/files/wibapatuji.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/5be05dae5b0d53e95dbdcc6b4c82fc17/83200653943.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021072209004473499.pdfIn PDF document text
    • https://watosaphotography.com/app/webroot/userfiles/files/20210814_234436.pdfIn PDF document text
    • http://legendtec-eg.com/wp-content/plugins/super-forms/uploads/php/files/r052iep9k0gtqa683j1jrtv8t7/82159579514.pdfIn PDF document text
    • http://ventmetal.ru/userfiles/files/7941926414.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a91fcf854e5---jokotodolupunewesaba.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b51547b1f7---70031720107.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16085e0ead6211---rotapudanudirewumeri.pdfIn PDF document text
    • http://fitviewer.biz/files/file/dabule.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/a902904f07a1833a6a0cf636d9c2789f/rasuweta.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/160984a18daf1d---suvexewofepetosivananaso.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/mm3i71aooatfi48mktmj181sv5/nigiteponagufezaj.pdfIn PDF document text
    • http://vietsaovang.com/uploads/userfiles/file/fudomujasetatobilowoxa.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc919cf9c5---14231342358.pdfIn PDF document text
    • http://tvkinter.com/file_media/file_image/file/17538992131.pdfIn PDF document text
    • http://tolltisztitas.eu/userfiles/files/fumalovaxilinux.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/14063793678.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/914a09380e9a172f5312de370d450b90/mujamegoberumodezodiwikiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=elinchrom+skyport+speed+transmitter+manualPDF 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_off0000d584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD584 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9B 11068 bytes
SHA-256: edb0f4bacbb970a7b601cbd68d7c0abf43fba090c4882185aa7061722b18f76f
font_02_sfnt_off0001072d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072D 17704 bytes
SHA-256: 87ce9db4452bb2f4a1d1a2d4dd2b416b1434e5babaf625373a999a01ad417211