Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bb5b3541a0b2517…

MALICIOUS

PDF

88.6 KB Created: 2021-06-27 09:59:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: eaef606ea909cedb81664eca662051a3 SHA-1: f6e53bbbde4c81cf44cfc130d9cf783aa87a2c1f SHA-256: 5bb5b3541a0b2517d3b8df3ad7cd15a941431694f49ab648f29ffc6e2356ab27
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites hosting PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is unreadable, but the heuristics and URLs clearly show a link farm designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • 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://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160905a1b5820a---nufezupaxoxepux.pdf In PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160ac7012f3c17---30893678461.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/zowejeli.pdfIn PDF document text
    • http://hainescentreasia.com/images/file/36880427471.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16092778fc34c9---parafikagexetabinir.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/xutudojokopegax.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c0bb0f00124---49842580792.pdfIn PDF document text
    • https://etimes.mn/uploads/files/28769628694.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/29456133051.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/b3d07be58e4a279d9266e11bfda329be/kosizes.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160caeb65ad11e---35599589563.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/6marbokb5d8cbhfb5bersdkgf6/dujozovukoz.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/39998865837.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/bbghbql907p0o6samarcsp0008/senesexonudis.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607a4cc11bfdb---40172907355.pdfIn PDF document text
    • http://cabin4kids.org/clients/0/05/050cd0fff5f75fdfd14851583cc0de74/File/bogusulig.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9f81a5616---32615753968.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088630f70781---58833853133.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d3598b081d9---wulexeze.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/b3dbb7d6d118c1491d55a0cc9456d05a/62131287619.pdfIn PDF document text
    • http://1careglobal.com/upload/files/95560803741.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b69eeed52db---wapakejo.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7010e9ed00---25219255485.pdfIn PDF document text
    • https://mimpi1pusat.com/contents//files/kazibupez.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/9f10799dcb4a30fea9ee92715891f8ac/35133217241.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=red+rock+stockPDF 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_off0000f902.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF902 10096 bytes
SHA-256: ac8a2ecacaedcd9340d19bfdb89fca71c55d91f1f4ddc3cf7d16ea3397c4ef58
font_01_sfnt_off00010fac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FAC 17420 bytes
SHA-256: 3bbf50359ca371a3f2cdb54bd7d7929fbf8f010e3954b9609c4b200669c7c117
font_02_sfnt_off00013d60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1