Malicious PDF — malware analysis report

Static analysis result for SHA-256 d716fba927bcef9e…

MALICIOUS

PDF

78.6 KB Created: 2021-06-13 23:07:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: a6bf260f9199b5381afc0b8367c8f10f SHA-1: 8eda041b00efdbb173703cd4f7d70a0e7f2326b4 SHA-256: d716fba927bcef9ee901db64962766e071158b6a8b5b22cd8c5d68dafac70a52
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://queure.ru/uplcv?utm_term=muniraj+singh+rathore PDF link annotation
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/b979806d8670f530eaf411254ffd94fd/68784983947.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160926a651723e---naxopufamititurenepo.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/kuruvisalupevovogujiz.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/3su3od1f0fhd3dhg6b81gj2fs0/92436295278.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c979b7b334---valumuxugerinubuse.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/daropetikaberi.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b37ec30a2---vanobagu.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/31b8ed6aa0015a383ed2950fc08ec433/85353243915.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a745b1958ff---19696573240.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070b8224e994---89167834230.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077364bd2d4f---60946319586.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/9f80667f61e317f1a012806e515b1aa6/83628665824.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/1f5c8bca780cd9588de2bf424adc3c08/99740049889.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858172a9ba4---3743628162.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d4c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C1 4876 bytes
SHA-256: a6942a810cb84ec4337689d341bfcf7f983aa5dabd8be1fea4a23f46f1da1d4f
font_01_sfnt_off0000e554.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE554 10668 bytes
SHA-256: d70892674513517d4b21f305b20524f8cf53de635b8887301e8c01e9e294282a
font_02_sfnt_off00010a11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A11 16208 bytes
SHA-256: 5c2345b24632f797a5cdb3f3f1a4d0cd6511aa851386282903ae793b0a996ccb
font_03_sfnt_off00011f62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F62 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378