Malicious PDF — malware analysis report

Static analysis result for SHA-256 8142cb36d6c8ecab…

MALICIOUS

PDF

76.5 KB Created: 2021-09-19 17:57:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 09021037187b5dcd9e4d2598780df71b SHA-1: 12dacb69f04b06fdff5e05a6405c97262f1d5cad SHA-256: 8142cb36d6c8ecab870ef24cda422ef8e1486649015c5eb75cf7be967a7f71bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS uploads or disposable domains, suggesting a link farm or phishing lure. The PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, aligning with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://huntic.ru/uplcv?utm_term=first+android+smartphone+in+the+world PDF link annotation
    • https://huaienclinic.com/uploadpic/files/65917162581.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/27033873290.pdfIn PDF document text
    • https://promenade-perpignan.com/userfiles/file/xusoripesubo.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b56064c2f8---bonokawoxubomo.pdfIn PDF document text
    • http://lechioutdoor.com/userfiles/file/23797599466.pdfIn PDF document text
    • http://chongros.com/userData/board/file/tonakedafaja.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/dekudozaxudotupun.pdfIn PDF document text
    • http://falerisztika.hu/tmp/59424188925.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/4833332bbb7b9c28e185eef9f8624296/dinubovoxikov.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/betareretulosobigivuvupi.pdfIn PDF document text
    • http://gavionescodeinsa.com/userfiles/zekenefirosodoxuno.pdfIn PDF document text
    • https://tpk-m.ru/files/file/dojekivedegaw.pdfIn PDF document text
    • https://yantrasearch.com/ckfinder/userfiles/files/nufebilolar.pdfIn PDF document text
    • http://nenkin-t.com/upload_img/ck/files/wofakusediwi.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16140f42d689fb---momomedeg.pdfIn PDF document text
    • http://msmzizkov.cz/data/dokumenty/selemarakojepatudukofexor.pdfIn PDF document text
    • http://noxsun.com/jingkelun/userfiles/files/20210916200046.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/75866344020.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/161365b4aaeb18---23495251055.pdfIn PDF document text
    • http://archiw.gbpopatowiec.pl/img/upload/files/modarivugitolukiz.pdfIn PDF document text
    • https://rarahil.org.np/ckfinder/userfiles/files/37829628346.pdfIn PDF document text
    • https://texigo.tw/upfile/files/2021/09/07/kuveranulinipevitiridije.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_off0000c75e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC75E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000df70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF70 17364 bytes
SHA-256: efd0f7d86e852dc199648ef6df9822b3fa91c7eacc2fac00ca7cc4467c81a4ff
font_02_sfnt_off00010c19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C19 10720 bytes
SHA-256: 6d6af882f25bf3e22f8b95b130a0aa827c6c0751e9fb27db0a0048bb3e940d7e