Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c9d7dabd7976686…

MALICIOUS

PDF

83.1 KB Created: 2021-08-26 13:29:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 299d2bd17c331e7c1bbf6bb51baed806 SHA-1: 52a51d41d6e43136b471964daee7457f21128beb SHA-256: 9c9d7dabd797668691b5fb9de65fdb746579a4456326db51125a7f716058fa30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a malicious PDF, as confirmed by ML classification and ClamAV detection. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The PDF_URI heuristic indicates a specific external URI that is likely part of the lure. While no scripts were explicitly extracted, the PDF structure and heuristics strongly suggest it's designed to facilitate initial access via phishing, leading to further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://krisoc.ru/uplcv?utm_term=xhubs+apps+download+for+iphone PDF link annotation
    • http://www.almansori-ye.com/almansorifiles/files/41970099941.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/legorofopimunobasa.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/o6bb0r7sub7pavic5dht5a8ccg/wakememejowazafarujinava.pdfIn PDF document text
    • https://net-mex.hu/ckfinder/userfiles/files/zeniri.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/sekuxu.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/nawerobetudakafagelagu.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b6a884f3684---nesigopanukeveba.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160efe9a968fca---2186305072.pdfIn PDF document text
    • https://empresa-venta.hr/files/wusitugik.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210523220845.pdfIn PDF document text
    • http://bethelcommunityone.com/clients/880032/File/sorixupurumerugijofiz.pdfIn PDF document text
    • http://bigband-ulm.de/userfiles/files/bujigo.pdfIn PDF document text
    • https://consurs.ro/ckfinder/userfiles/files/33948964063.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16082455a2e2b3---48977951797.pdfIn PDF document text
    • https://pindimana.in/uploads/file/laboje.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/51909832286.pdfIn PDF document text
    • http://vip-cond.ru/userfiles/file/49535762126.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/d5958ce2c2c45e8963e129ef6acbeb1c/xugijomunagosopeloxeruve.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e18f264b1bc---xusurimur.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/vkme4eedbmi4lasvtvfr6bihbb/fimekador.pdfIn PDF document text
    • http://visit-pune.com/userfiles/file/68043480143.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/userfiles/file/83895819684.pdfIn PDF document text
    • http://berallebags.com/UploadFiles/FCKeditor/20210618014257.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/7d5f3953d5b1a27d250db5f039cfb9b2/dalolotenojulafapa.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_off0000e101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE101 16876 bytes
SHA-256: cb75d88019e5e684b4ec454892cb1730bb757b9aa8ab1bf5425c16cc5be178b5
font_01_sfnt_off00010c7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C7A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12491 10832 bytes
SHA-256: a2d0c46bcb213e7a80feb5645740d104622512b559454de63cc52f26b882e45a