Malicious PDF — malware analysis report

Static analysis result for SHA-256 8943b220c9471b56…

MALICIOUS

PDF

87.6 KB Created: 2021-08-13 19:12:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5bc348aad4ada089e6e41f449de84e5f SHA-1: 4773b98c0dc816d0abee92a32fe24aac3ba99feb SHA-256: 8943b220c9471b563d64f043ee83886771e7e13d407026fb5d78ac1a12f0bbd8
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicate a high probability of maliciousness. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, suggesting an attempt to distribute phishing content or further malware. The document body is unreadable, but the heuristic firings strongly indicate a malicious intent to redirect users to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607185a3e20f2---vimukasizowitipifepexi.pdf In PDF document text
    • http://harchovyk.com/userfiles/file/gafavotawugagenojewoxugim.pdfIn PDF document text
    • http://scbczy.cn/up_files/file/20210610_095110.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/bo9r1fes1v861da0fedi35u942/85442229980.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/m2go6mrptekgmd8rc00ak58sk3/dasavotuzowinigosupobopek.pdfIn PDF document text
    • https://afayl.com/userfiles/file/meterasejasomoxum.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160ab131b7dfd5---95168272046.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/gonuxebosekex.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/kokikejepewuwagalamegug.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/lkquekpdtalplbq20oo1qrj141/tedew.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/file/nogefiratobixi.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/25243380737.pdfIn PDF document text
    • http://123podkrovie.sk/editor_uploads/files/muxudivegot.pdfIn PDF document text
    • https://htapigroup3.com/contents//files/kolavesilupejeve.pdfIn PDF document text
    • http://chinocorporatechallenge.com/clients/6216/File/luwenakufokowe.pdfIn PDF document text
    • https://signika.pl/Upload/file/61792233914.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/64350226817.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/1846422608.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/an0tl6h2ge9e5snhlqtohuoma9/vakikisikavuwojowesi.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acd23a1f3d8---93441045711.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/7d312acaeb359732998e007d6e29d3f7/75979666076.pdfIn PDF document text
    • http://55thocscompany.com/clients/62662/File/lexowemivavopipuvox.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608657dae6394---47964974913.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/c65a045aa3eb8b61c345f8d534ed6c3b/35724136460.pdfIn PDF document text
    • https://navliecky.net/userfiles/file/25981697092.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=what+is+debit+note+and+credit+note+with+examplePDF 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_off0000f35b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010b6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B6D 16784 bytes
SHA-256: 07cdb87b5b0fb720557819dd92877114613bbfe26f3080627ca4a70f6817ad6d
font_02_sfnt_off0001370f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1370F 11100 bytes
SHA-256: 726dbe66850557140050e1e93884972d086b3af86763bf977aa30dff92ffd869