Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a8f8b5372f5aab8…

MALICIOUS

PDF

105.9 KB Created: 2021-07-24 23:57:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: 4297dcff0eb6031011485a4f0954d7fd SHA-1: b0d30bd62f4c59dc0a8a02c2c9beeccef272cc5c SHA-256: 4a8f8b5372f5aab8bd63ee6705369a4cf213fd1483b37c92c96b0e247e5d5e07
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a callback-phone (TOAD) lure. 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 0.9867

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/pkshqr5u3lj5kfqp05ermv6jd0/vepabiwisejowunubava.pdf In PDF document text
    • https://oklogistic.lv/upload/file/31259639817.pdfIn PDF document text
    • http://av-jet.ru/userfiles/file/fakefinexiziterugigudumo.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/fdb1972e38aea60657f2d7c00ea35188/6421143582.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16077d27217094---nudodogawonaredok.pdfIn PDF document text
    • http://artospace.com/pics/file/razek.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/5a119c1f86626fa03cdff8c0568e2a81/xiperi.pdfIn PDF document text
    • http://zlato-stribro-investice.com/upload/files/fujotatepuwemoba.pdfIn PDF document text
    • https://idd.no/ckfinder/userfiles/files/gugiwobemuboboza.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/6529538228.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/3969c0a834619a4ba54ce4a55a6d50b3/gigazi.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/162def7247e20b017a5e5fb7518cb2ef/deririlugo.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba4b49981b2---korefagagujojo.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160875e8202fca---doralulezebegos.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/b539b00516ea45b6b39c71754ea54579/86941730842.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e85535a52---33875697347.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/ebd3917f79fcb656f939393b6c833472/59754283062.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a64c9eee8d6---54117865051.pdfIn PDF document text
    • https://evenimentecastel.ro/wp-content/plugins/super-forms/uploads/php/files/j1orjl3stvmu9st391nd0dic9j/19052553369.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d41a2b0e25---12553931587.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16099c7a9a8d8f---tozalol.pdfIn PDF document text
    • http://www.rafaellucenaehijos.com/ckfinder/userfiles/files/fubimebovodubijikofosu.pdfIn PDF document text
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/k8a6l4av3vnpbcpisjmafaqrta/28969783542.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/n65i6fd7qit2itskset9a282s7/60447406502.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/76144153241.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afdfebc8ab3---navomiwagetejato.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd6bd67c17a---bikilugizusukan.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=sennheiser+rs+120+service+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_off000139c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000151d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x151D5 18508 bytes
SHA-256: d91115699eb217616bbc193f07aeb055a79f6e7c49b1b33a47ac63e9ef6649a4
font_02_sfnt_off000180ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x180AD 10812 bytes
SHA-256: 5a5b8385e76378a4a83dc61ab0c1878b013d8e50d8dbf75fdea4441e918826f4