Malicious PDF — malware analysis report

Static analysis result for SHA-256 c10957d4ab2a06a4…

MALICIOUS

PDF

75.8 KB Created: 2021-09-06 16:25:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: aa5e511685f885a31cfb1019689eeafb SHA-1: 70e22e35d9e470b125e0880a9dcdac3c3523e8f8 SHA-256: c10957d4ab2a06a4e612c14f75ca2fcab80c50957393d123dbd98852f89ac720
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm designed to redirect users to potentially harmful content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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://irlanc.ru/uplcv?utm_term=diabetes+mellitus+signos+y+sintomas+pdf PDF link annotation
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcd8402f68---57998031837.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/dedodelujedesobesun.pdfIn PDF document text
    • http://kozelskadm.ru/files/uploads/files/45547723860.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202108051052201368.pdfIn PDF document text
    • http://locnuocvietmy.com/Images_upload/files/lokaboxumigowetaja.pdfIn PDF document text
    • http://dhleisure.com/ckupload/files/32503444611.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16072ef36cae0a---67621070183.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af6bb49dcbd---21237648858.pdfIn PDF document text
    • http://investin-khj.ir/ckfinder/userfiles/files/limamizepoxanixe.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/57071439584.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xewibunoxezinirasiw.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160b22f6450cc3---54207094604.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/96a7e30aac27cd1d3219e4e7cd971c96/56472470890.pdfIn PDF document text
    • http://bukharaalpharetta.com/sites/default/files/file/40818770922.pdfIn PDF document text
    • http://synergyproperty.com/images/files/fanenevixipewozo.pdfIn PDF document text
    • https://grancom.by/upload/docs/pividugejibeforazug.pdfIn PDF document text
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/6i67nkj1ncr2ql453cjnoncr78/58954111070.pdfIn PDF document text
    • https://apskarota.org/userfiles/file/77380805762.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/3v0cnl2nmvlol50i83q2ml08vg/34135177613.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/meparoxekom.pdfIn PDF document text
    • http://www.aluvascientific.com/UserFiles/file/83007276542.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/c6c7155d15150ffc4e4a80af2f3d8160/90740833334.pdfIn PDF document text
    • https://ntwbearing.com/UserFiles/File/gexoleli.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_off0000c2d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2D8 11096 bytes
SHA-256: c58ab5e50ac69bd83feafe86ec472976e8be3eb5143a5ade3b6ddc8c69b3370a
font_01_sfnt_off0000dc56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF468 17864 bytes
SHA-256: 1f80ded200b27b4ebe32b5f34cbd287e2dbc229984ad9f861de94ac5b54b606a