Malicious PDF — malware analysis report

Static analysis result for SHA-256 5363f5eaa1cb1833…

MALICIOUS

PDF

76.7 KB Created: 2021-08-16 20:43:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2461b935fc4c5d07bd3bcdc83b175bf7 SHA-1: 5ce2b8d7bc3b18a22d259f83e3c2c59f3dfe7284 SHA-256: 5363f5eaa1cb1833c80a1450b17ff7a9ece37d2ae0f1ffaf63d7b0bf37580266
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://bleikss.com/userfiles/file/taxavikove.pdf In PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/divupifepavaputabumi.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/mesemegekavovajogo.pdfIn PDF document text
    • https://smartcirclegroup.com/userfiles/file/30939571768.pdfIn PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/3410052795.pdfIn PDF document text
    • http://iphysiology.ru/upload/sawimewonono.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/tenilozexufumepefofo.pdfIn PDF document text
    • http://healthywithhart.com/res/file/newomuperegovimu.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/59106307413.pdfIn PDF document text
    • http://techhssilverbuffs.com/clients/61416/File/tepisilimizimijizawamis.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/lerasanopamemetenozibofo.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/2332914353.pdfIn PDF document text
    • http://123podkrovie.sk/editor_uploads/files/27585938793.pdfIn PDF document text
    • https://himalmanpower.com/ckfinder/userfiles/files/zoxexut.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/52e79349836f82f97c0932f23680be49/kefaxuzaxatobimixufoxus.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/79935576251.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160be59739137d---4974326023.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/gemuwexuredofoga.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dfe8f79523---8950765924.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/64760093932.pdfIn PDF document text
    • https://mimpishio2.net/contents//files/13753725709.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16075c35c7fcd0---75455603998.pdfIn PDF document text
    • http://ckpak.com/fckeditor/userfiles/file/40232168467.pdfIn PDF document text
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078b45861db7---lexomuvuwuvawuxasul.pdfIn PDF document text
    • https://gionggiacam.com/ckfinder/userfiles/files/70336663272.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160838ff3ed9a5---65697545825.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=what+to+put+for+hobbies+and+interests+on+a+resumePDF 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_off0000c8b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B0 16144 bytes
SHA-256: 047585d465545a3db6d613a654a16f4335c4aa04e2cb262f708f9f02009897d0
font_01_sfnt_off0000f272.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF272 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A89 10952 bytes
SHA-256: f2e7ecb4d4307012a87359aea0175f0148076797fe8895d2e12b7d4b34f090ae