Malicious PDF — malware analysis report

Static analysis result for SHA-256 523215934e739443…

MALICIOUS

PDF

70.2 KB Created: 2021-09-14 07:20:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 544d46d947f39ada66d457c2542759a1 SHA-1: f15654672518391c120b635d5c6a5575894c7855 SHA-256: 523215934e739443f654edfedd7256d75c62194bb6e2d7514d491ec1bddedebe
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing 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 for phishing or malware delivery. The presence of multiple PDF links suggests a multi-stage infection or redirection chain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://ciarajewellery.com/editor_upload/file/kabosewabugujuliku.pdf In PDF document text
    • https://przyklejki.pl/userfiles/refibi.pdfIn PDF document text
    • https://mywayrtk.com/userfiles/file/66225484154.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/df2af2e58d02993672bde8233465c39c/23582143467.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/7vpc116ojed9e5ctjvcu6k5q65/depulenaz.pdfIn PDF document text
    • http://zagazzo.com/userfiles/file/35488435973.pdfIn PDF document text
    • http://adimhukuk.com/resimler/files/xixowirazufopuriki.pdfIn PDF document text
    • http://proart.by/media/file/kureki.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/9907730002.pdfIn PDF document text
    • http://co-mit.com/uploads/files/kapuz.pdfIn PDF document text
    • http://gabinetortodontyczny.eu/userfiles/file/34968983570.pdfIn PDF document text
    • http://gonzagafood.com/userfiles/files/32860087125.pdfIn PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/43704476303.pdfIn PDF document text
    • https://bomnuocebara.com/quangbasanpham/app/webroot/upload/image/files/15705722660.pdfIn PDF document text
    • http://kesherisrael.com/uploadEditor/files/33733241296.pdfIn PDF document text
    • http://www.lovebliss.tw/UserFiles/files/dutoxixenumananagugaberal.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f730df340f---foluxugizizefafoja.pdfIn PDF document text
    • http://ibtaker.ps/userfiles/file/varepafiwesaruzel.pdfIn PDF document text
    • https://marathonlaval.com/userfiles/files/jofepivapam.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/fasoximutotugoresarur.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/j15dgj6n1h2ou877v195i0abp1/wunetelumilotelovovefu.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/37746768867.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/tezerajow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=youtube+widget+download+androidPDF 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_off0000b4e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4E8 10564 bytes
SHA-256: e2be99fc24feb8fbf5036b6f1dd8338f3e55660b069702b4c79364aa290cf18a
font_01_sfnt_off0000cced.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e4ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FF 15220 bytes
SHA-256: e4eb519b9a83420ca02e78a05c0fd8d1093f9963bfcc2583aebe27c0391859ad