Malicious PDF — malware analysis report

Static analysis result for SHA-256 872907c1c85868bf…

MALICIOUS

PDF

79.8 KB Created: 2021-10-11 11:56:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7ac7c957ab0f69fb1a74c920f208bde3 SHA-1: 44d4325c38811765fbdd695b36308ba70299cb42 SHA-256: 872907c1c85868bf17e3eef0015113fbc3af62f22e9f46cbb8fde53a1b20c876
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to domains that appear to be compromised or disposable, suggesting a link farm designed to distribute malicious content or phish users. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. While no scripts were explicitly extracted, the PDF structure and link farm heuristic indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://www.sloepverhuur-debiesbosch.nl/upload/files/musapafukir.pdf In PDF document text
    • https://sim2007.com/files/11942023412.pdfIn PDF document text
    • http://tao-ssct.org/data/upload/file/93309615404.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/nefozubopovuxu.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/11159923252.pdfIn PDF document text
    • https://ferropula.hr/files/kafuxopezikosugejunerorub.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/sabis.pdfIn PDF document text
    • http://polaryachtmanufactory.com/res/wysiwyg/file/pusopixetozat.pdfIn PDF document text
    • http://megamento.com/_UploadFile/Images/file/bajoro.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/20ed9aceb81eb8b4938dfaf66cac171b/70495641217.pdfIn PDF document text
    • https://elesud.it/img_pagine/file/purowexovigoxap.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202109/file/1632013168.pdfIn PDF document text
    • http://qdxqw.com/uploadfile/file/wowexumefamixedizazepi.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/8fa04532c420c8503551bef0215bc115/4488461558.pdfIn PDF document text
    • http://productinfo.in/konadnew/userfiles/file/95437245790.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/43663876368.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/jodasab.pdfIn PDF document text
    • http://vitacanes.com/uploads/files/38746510201.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/nuriromasamitid.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/latesiza.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16144b55c103af---buvorizuwazedogasekulese.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/1f14dbfcb3b85d2f0659586198fec400/86963494812.pdfIn PDF document text
    • http://raegcafe.com/uploads/files/dapakulebisefunodike.pdfIn PDF document text
    • https://vietucmould.com/img-vietuc/files/jibabevufuzafod.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/be9ebd54f16d021b18908ad4ad8705fb/xibemabafomame.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/896FEnmJZlk/uplcv?utm_term=self+introduction+for+class+5PDF link annotation
    • https://www.posluh.hr/ckfinder/userfiles/files/zivefuxi.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_off0000d628.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD628 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3F 10776 bytes
SHA-256: d88ab44d7fbb27eeeef05d3c070e28037207ba2875ead191e3f1811ef0598f3f
font_02_sfnt_off00010730.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10730 16604 bytes
SHA-256: 719c71be526f692d759b6ca79a6dd5225d42ec753ff9be69faaf4936bb32121f