Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c08ea05d3148679…

MALICIOUS

PDF

79.9 KB Created: 2021-09-18 23:41:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a4e8ad744b507b2dcb4ca96ea5b913a9 SHA-1: 31f4bff1270d28e56a1832d697eae71f42321b66 SHA-256: 9c08ea05d3148679a9e82ce47f5f0d9fac489160dab59699367f5161bb24e476
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which point to other PDF files hosted on potentially compromised websites, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://laborke.ru/uplcv?utm_term=how+to+turn+off+location+services+android PDF link annotation
    • https://cuatudongnhatrang.com/uploads/files/98680520282.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/zevoxamewulepase.pdfIn PDF document text
    • http://www.hz-kontejnery.cz/ckfinder/userfiles/files/74514654060.pdfIn PDF document text
    • http://missteenqueenuk.com/userfiles/file/sasagokixamoneze.pdfIn PDF document text
    • http://topoint.cc/userfiles/fckFile/20210916165416.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/watavimufuvomegutusap.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/ketulaga.pdfIn PDF document text
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/65199458576.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133a7fbd3289---vawom.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/jamezawuzoxusedabodokeg.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/gibaweledomaxetuko.pdfIn PDF document text
    • http://wildpflanzen-planung.de/file/xumeze.pdfIn PDF document text
    • http://xn--b1amishc2fb.xn--p1ai/ckfinder/userfiles/files/dowijekaxubiwuwoji.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/bobobu.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-9-4/20210904010358834675.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140c3778fd67---jijifafexadijonilol.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/f4899870d01e628f184487faa66509d9/50101253709.pdfIn PDF document text
    • https://podgoricki-klub.me/userfiles/file/36242380602.pdfIn PDF document text
    • http://luligang.com/ckfinder/userfiles/files/nagitetufizuwudu.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/jujenibisexosusedobu.pdfIn PDF document text
    • http://pes.edu.mn/ckfinder/userfiles/files/bogukovosivururiwija.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_off0000d4af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4AF 17032 bytes
SHA-256: 48cf7128471f51a1fabdfb34d2e0b4f9a579470cc6bfccbf398258d9495781d2
font_01_sfnt_off000100d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E9 10712 bytes
SHA-256: 65df3955fabd6d44ff3dffd3b96b0de0acc60b22a1cd5eea525c6e337a4cd682