Malicious PDF — malware analysis report

Static analysis result for SHA-256 50fe2151d58d4db2…

MALICIOUS

PDF

72.9 KB Created: 2021-09-04 17:20:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2877538f125d7037f80036b3ccc0d8bc SHA-1: 04f317c0560d84aaccc284a1415a013c9b418484 SHA-256: 50fe2151d58d4db2d9be1d93cfecee47a9cde9ca2af7a722c1edf88911f83391
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 CMS upload storage or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the primary attack pattern involves directing users to external malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://irinka.org/ckfinder/userfiles/files/51770957346.pdf In PDF document text
    • https://underworldgear.com/upload/users/files/kipubepevozupasanep.pdfIn PDF document text
    • http://chistogood.ru/admin/ckfinder/userfiles/files/xonapokafunatokesanol.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/43749834652.pdfIn PDF document text
    • http://growlink.biz/userfiles/file/18840726823.pdfIn PDF document text
    • http://iteequipment.com/clients/65150/File/50061239391.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b26af3ca17d---lazupibupevoxusodejew.pdfIn PDF document text
    • http://anvlaw.com/userfiles/file/tepewi.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/239247d0fc9e6b2d6985c8bb29f39797/89002649919.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/4579c754454628a6d9efda057577c25b/kabapinitobefavusimi.pdfIn PDF document text
    • https://mbzgogo.xyz/web/img/podborky/files/72176425885.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5ce645768---dosovufevujezizopajo.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d9489288a2b---sunejenanorujuxutimizuv.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a05d6f8f154---fafujagefokogijav.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/4240781948.pdfIn PDF document text
    • https://topaldanang.com/uploads/image/files/pisinofifajifovupame.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161153ebcbe061---tekufomofubife.pdfIn PDF document text
    • https://www.aceitedeoliva.com/wp-content/plugins/super-forms/uploads/php/files/f4f6e2928d8a4922af3ee56113c7893b/rutisiriputasu.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/161284f0af2f82---nalenigizelonorupup.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/katezarugufikuvesu.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/33968222943.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5f4778352---diginebexa.pdfIn PDF document text
    • https://mangonebike.com/uploads/file/fapopasusutugezazujekiju.pdfIn PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/94846452534.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=comparing+lengths+worksheets+year+2PDF 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_off0000bb48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB48 15984 bytes
SHA-256: 35c685938c2e1d2761049ded654be3cffd04eb39a7e0844f018e3e1379035e1f
font_01_sfnt_off0000e428.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE428 11144 bytes
SHA-256: fa906f8e58f4aa2afcbcff85a14f80d6a069543a7c168be9148d47eed1dbcbe3
font_02_sfnt_off0000fe23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1