Malicious PDF — malware analysis report

Static analysis result for SHA-256 9610b74aa6ad86c9…

MALICIOUS

PDF

69.7 KB Created: 2021-09-30 21:53:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 6a1b6b5c80eee14eda497ffc4343805d SHA-1: 73a5bb5c10988f54a5187290567c6bbf992ec9e1 SHA-256: 9610b74aa6ad86c90d66de417563dcfe3b777e55f0f034b06fbd06f90b613268
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm or SEO spamming operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://kamarkosong.com/contents/files/pokinebivojixotiwaroga.pdf In PDF document text
    • http://rzn-house.ru/upload/file/goduguvepe.pdfIn PDF document text
    • http://idcla.net/upload/files/posimabawewerujofapasi.pdfIn PDF document text
    • https://red-adlay.com/upload/files/jinovejag.pdfIn PDF document text
    • http://fittbikese.hu/files/file/19495004545.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/a007509f938f36a0b59caae905272e4a/7775256279.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/fudozezuwavitonejag.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/16144039fc2eae---galifisijewazorujupedav.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/sedezidadiropegukare.pdfIn PDF document text
    • https://shellserva.nl/docs/Image/file/kezuzuved.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/15455576987.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/baxaduko.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/2022586492.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/68835471433.pdfIn PDF document text
    • http://spbmedax.ru/sites/default/files/uploads/wuxixafafexelogu.pdfIn PDF document text
    • https://sibirprokat.ru/ckfinder/userfiles/files/89364303674.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/47386040400.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad25578263---fesov.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/fuvarem.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/a2e2e46d609b6a33964265c2b474578b/96924413304.pdfIn PDF document text
    • https://biblioteka-koneck.pl/ckfinder/userfiles/files/pusizurawagugorewesokeb.pdfIn PDF document text
    • http://caopump.com/admin/userfiles/file/pabuxebekazize.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=cool+math+games+powerlinePDF 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_off0000aeb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c6c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C7 10816 bytes
SHA-256: b4217b2abd3dbf5efa5eb626cb390fd2ff10d067853ea9c7b77e754abd7efe4f
font_02_sfnt_off0000dfa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFA0 16416 bytes
SHA-256: 59aece032e3d0c2408b9e2f702443076364d3ce91822774013de491411e38460