Malicious PDF — malware analysis report

Static analysis result for SHA-256 3358382843872ae2…

MALICIOUS

PDF

81.1 KB Created: 2021-09-04 08:50:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: fb8e2be276d658da1d1dac705f1e605c SHA-1: db2754d54ea0bfc6c1f57e2536500967e4d33212 SHA-256: 3358382843872ae28c1edbecab65785f99ea6dd253a15733dcb49a2c68731970
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 0.9981

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://wpscrm.in/uploaded_files/userfiles/files/nirerusi.pdf In PDF document text
    • http://ecohort.com/userfiles/files/76785227208.pdfIn PDF document text
    • https://songhong-thudo.com/img/files/giradaminukora.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/28545159875.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210704_C72FB738AF0D2A8D.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/19746669172.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/61288884488.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/zazegelapuzirijamexem.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/75e78e8a958ee97c50f2d281bf25dd61/bomekimemopuvujo.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160921209bdba9---58080983896.pdfIn PDF document text
    • https://beauti-full.ru/uploads/files/pekutusalubewurimotakolo.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/bopozitejadasekivafemu.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/wonorer.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160848074bfea3---53847425862.pdfIn PDF document text
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/71360765390.pdfIn PDF document text
    • http://apluskleaning.com/admin/images/file/82871907685.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a679c021273---bosuzamowe.pdfIn PDF document text
    • http://capital96.com/userfiles/file/goxukikuxoralajesoxe.pdfIn PDF document text
    • https://ferdavagnar.is/images/fck/file/77811362299.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16071cd1362316---kexigenumufowi.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16102eda862fc2---fozemuxazejazefusu.pdfIn PDF document text
    • http://effekt-film.de/files/file/89343107788.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=amplified+musculoskeletal+pain+syndrome+pdfPDF 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_off0000d866.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD866 17144 bytes
SHA-256: 1fe15ab943f5370331785e56733c743fce5e1429d898a659c9584af7f3b2f15f
font_01_sfnt_off000104ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104CA 11068 bytes
SHA-256: 98ae3ace66429533bdccaffee94bdee5b1c7619664950170b87bb17f8a10a7e7
font_02_sfnt_off00011e99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1