Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb4db16f1a110719…

MALICIOUS

PDF

80.5 KB Created: 2021-09-19 00:53:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 66f87e8e0f190fec801efe8210d5e81c SHA-1: 243d28ce9b1f9230660efc258f503ba7b3d15bba SHA-256: bb4db16f1a1107198cace2fe9bfc012f8b8294d7753aef8047f6d77e84d20c86
156 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many of which point to compromised WordPress sites or domains that appear to be disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to phishing sites or download further malware. The document body is unreadable, but the link farm structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://asiapharma.la/files/files/maleporinebum.pdf In PDF document text
    • https://aquafilling.com/userfiles/file/dugubo.pdfIn PDF document text
    • http://uteambio.com/upload/files/36061368273.pdfIn PDF document text
    • http://zoldjogsi.hu/uploads/files/82512431160.pdfIn PDF document text
    • http://flyingwedge.com/uploads/assets/file/febuzosaguwuzepijerefed.pdfIn PDF document text
    • https://vilnius.cvzona.lt/resources/img/files/xedexutavo.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/31816418640.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/07e601f80c327fb5062793872c472a2c/wafusoderokubivekoz.pdfIn PDF document text
    • http://hanasushipickup.com/uploads/files/xivipofafifolewuzo.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/46720c57f33ed3e2bcf4ccb3b07e2506/53779875930.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140256cbf573---fujaz.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/rolatesafig.pdfIn PDF document text
    • https://oklogistic.lv/upload/file/76589571193.pdfIn PDF document text
    • http://xaydunghoangthanh.com/img_duhoc/files/49931964277.pdfIn PDF document text
    • http://likebarcode.com/image/files/20210913_220940.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/87932644856.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/28663445906.pdfIn PDF document text
    • https://coluer.ir/documents/file/71059447839.pdfIn PDF document text
    • http://shopgraeagle.com/ckeditor/uploads/files/jamofewelewetorirafumexa.pdfIn PDF document text
    • http://watch62.ru/files/files/36300669392.pdfIn PDF document text
    • http://yucehukuk.com/resimler/files/ritisu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=hogatoga+free+call+appPDF 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_off0000d8f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF102 16996 bytes
SHA-256: 5bce65d5ab00a98b75e8ef2ead41ce6008a698d8448608fe12607f6a31aa6732
font_02_sfnt_off00011d2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D2E 10280 bytes
SHA-256: d1894e5bae8d95cfd760a2c65089b2dbfed2cfc85148743671747b9f3feecdaa