Malicious PDF — malware analysis report

Static analysis result for SHA-256 676bffc690772e0c…

MALICIOUS

PDF

84.5 KB Created: 2021-09-13 22:36:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e7409db19a4d8bc59a7cd0981d8fe18c SHA-1: 718bc6725c4cdb8915e742dee24d437eef0c1c1f SHA-256: 676bffc690772e0c78a76bb99970c071efe8f6a6596c13dff70b68f719817004
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by an ML classifier and contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting. This suggests a link farm designed to redirect users to potentially malicious destinations. The presence of multiple PDF link farm heuristics indicates a deliberate attempt to obscure the final destination or to distribute content across various compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://dmitrovka-zn.ru/admin/ckfinder/userfiles/files/mokewuwidedokosazova.pdf In PDF document text
    • http://michalpavlicek.com/uploaded/file/xebukusexa.pdfIn PDF document text
    • http://sin-hua.org/userfiles/sisazuguboxeditolaziga.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/5976775875.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/161392d361d470---67308701127.pdfIn PDF document text
    • https://atlanticcompact.org/userfiles/files/jerufitebeligagominavi.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/forix.pdfIn PDF document text
    • http://tecksco.com/upload/files/11694209866.pdfIn PDF document text
    • https://parkettworld.com/upload/files/pimasesujikenutubadova.pdfIn PDF document text
    • http://vattuxaydunghl.com/userfiles/file/vuved.pdfIn PDF document text
    • https://istanajp.com/contents/files/kejipimenikaruparoxix.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/16138d0d506dec---segepitinomumoz.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/56562480585.pdfIn PDF document text
    • http://rideco.hu/upload/file/79663347291.pdfIn PDF document text
    • http://idcla.net/upload/files/xapuzozuzusen.pdfIn PDF document text
    • http://copingconversations.com/userfiles/file/52520178989.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/15393889911.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9b7527756---zajivagarebegurijomin.pdfIn PDF document text
    • http://fese.in/ienupdimages/images/files/moxapivo.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/jovomibejud.pdfIn PDF document text
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/10551595067.pdfIn PDF document text
    • http://bigbazar.cz/is/images/FCKeditor/File/15796453611.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=which+country+has+largest+territoryPDF 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_off0000e4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DA 10716 bytes
SHA-256: 60f5d28a10da08c8f52df8d9cdc398d8edb7ab2c4562015b31fd9ff37986e5c3
font_01_sfnt_off0000fd7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7D 18052 bytes
SHA-256: 5c1c5f1de5cdccc3236578b2315ebd5a02208c847252ea46565998dbf63cf4fb
font_02_sfnt_off00012c7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1