Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc0b9e22ecb27266…

MALICIOUS

PDF

76.0 KB Created: 2021-09-16 06:07:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c71789dfde4da332d9b2df5aee03e813 SHA-1: 656dd70d61bf2bb57ac6460ec1d4f19eb68cba57 SHA-256: fc0b9e22ecb27266f742fe5c5bff00ba0417ac953b827716c1884d02c99a1e49
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains numerous external links, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristic firings strongly suggest an attempt to lure users to external sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://inwebjor.ru/uplcv?utm_term=how+to+install+apk+on+android+from+pc PDF link annotation
    • https://www.aukuras.org/ckfinder/userfiles/files/xojiwukej.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/15934015501.pdfIn PDF document text
    • http://www.ciesol.com/ckfinder/userfiles/files/jalag.pdfIn PDF document text
    • http://fge-service.com/userfiles/file/64479085986.pdfIn PDF document text
    • http://specialcats.nl/media/files/susemur.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16140bc03df329---refilolinijuxopa.pdfIn PDF document text
    • http://panda-es.tokyo/yamituki-n/uploads/files/37734288819.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161322478d8e0a---79735195724.pdfIn PDF document text
    • http://krupongs.com/images/file/41498247810.pdfIn PDF document text
    • https://shevian.com/images/file/14344404958.pdfIn PDF document text
    • http://abdon.madteam.net/ckfinder/userfiles/files/9996026806.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/vivikekuvosusefapamuzuv.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/lubifixu.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/a51245be87c599e3149e2aa523f888fc/47185836102.pdfIn PDF document text
    • https://factorysales.com/userfiles/files/21413979568.pdfIn PDF document text
    • http://atomleasing.ru/media/File/zupitupataj.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1631090779.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/3b5303b4d096f75bea93a302702d3124/43330432337.pdfIn PDF document text
    • http://hkacca.com/userfiles/goxevipilukeboxusuw.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210910140857.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/bdf485859fb6c303dfa49752d4e267f9/xeton.pdfIn PDF document text
    • http://officegate.biz/admin/fck_upload/file/60514918963.pdfIn PDF document text
    • 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_off0000c4c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4C8 17144 bytes
SHA-256: aad8daad2a254230ce05ba92187d70f8a82b0de87f2afed026cffd126fe150d0
font_01_sfnt_off0000f126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF126 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001093d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1093D 10820 bytes
SHA-256: c6467081259137611c5c235a3f767aad100d08265812712236fb018b553e260b