Malicious PDF — malware analysis report

Static analysis result for SHA-256 79ab5f30011f9351…

MALICIOUS

PDF

100.3 KB Created: 2021-06-27 13:08:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 11320d60e56c65993a90d6c1c2744402 SHA-1: 087c1cf7d505ccbb8f779316fb08efbe2ed8a51c SHA-256: 79ab5f30011f935139b58ca25594251096beb4178798f066ce7ae397fcd8c030
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting it functions as a link farm to distribute malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for human readability but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://ajitcoatings.com/uploads/81834555602.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a3834327f---13609061090.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606eda47a7552---76716138524.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1c80c43c2---fepokukimusemavelifefi.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/9klfu17e7q39dfqse73jvhmaer/16838383413.pdf
    • http://dekoblickfang.de/userfiles/file/deruresipo.pdf
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/repasurofogovutegupoz.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-1/20210501042839561542.pdf
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/d20e968702720a8e88b826abc56b570d/wimuzizegawapide.pdf
    • http://1utilaje.ro/mm/file/maleb.pdf
    • http://ash-graphy.com/userfiles/file/dexuzonutavutusoj.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/mlbhs56hi96bugmqdla4u0o2uq/bikobowifigiponejipibapuf.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/6a6ba0e07f0985833462ddca9d44fbf9/gusowapagep.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b865caa8d24---rujujesibafusimifonitix.pdf
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/e38a5d5c46029a628b7bd0d6b5437e91/kalamove.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/2f0b4c637353d619f896020f355a7b53/54509350225.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/hpvjc5t3u46f806atbooha4n77/85573156141.pdf
    • https://tramtron.vn/uploads/files/files/gotirolowoxebu.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe842e6d4f---feliwunamaxebuw.pdf
    • http://artin-intranet.com/ckupload/files/37777658129.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/1mloclvjrr315k01jppn8sh9k4/89664785709.pdf
    • http://pensionpoint.cz/userfiles/files/74438497765.pdf
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/de49c0792683f19948d30222e9b72e98/70476882670.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca553b0e27---85351191462.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=love+always+hurts+quotes
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000127db.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127DB 16792 bytes
font_01_sfnt_off00013fed.bin
38ecd6d33773a47eeec53aba7346b5ea214494f68e681d5ab7c5cb8aaa2a61dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FED 17236 bytes
font_02_sfnt_off00016c37.bin
c6f048b65dbfd885793074cacc76c01f2b6076e0c13aa0878fa7c1db5fa77b53
pdf-font-stream PDF embedded font (sfnt) at offset 0x16C37 10480 bytes