Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4cb19c77398c6b8…

MALICIOUS

PDF

78.4 KB Created: 2021-09-13 20:27:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c7aa2362f5ca297bac756cbe0b0d9e38 SHA-1: 0ac27066ba50e833e83f1d09da30ad2df94e0f3f SHA-256: d4cb19c77398c6b80feda6eb314a921c746a2aebb524b26bf7d68aad8a4e4bed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://queure.ru/uplcv?utm_term=tap+tap+apk+open PDF link annotation
    • http://ph-easycome.com/userfiles/file/miserujej.pdfIn PDF document text
    • http://infinivideo.hu/sites/infinivideo/files/72290243515.pdfIn PDF document text
    • http://nataliashishkina.com/userfiles/file/lanujep.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/31532494257.pdfIn PDF document text
    • http://jarauwerdaenzn.nl/userfiles/file/44237842528.pdfIn PDF document text
    • http://emblem4home.com/UserFiles/Member/File/87284209943.pdfIn PDF document text
    • http://xsjsbzrw.com/uploads/files/15998433105.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/57582500574.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/30569416381.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e367d5b8b2---fiwiruxawexu.pdfIn PDF document text
    • http://fatimaartwork.com/userfiles/file/fusofefanod.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a13e43f2cc---21055463514.pdfIn PDF document text
    • https://kochitaxirental.com/ckfinder/userfiles/files/50769607877.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c65d79f15f---10707030517.pdfIn PDF document text
    • http://hdurmuslar.com/images_upload/files/modetasegaxirox.pdfIn PDF document text
    • https://luckysurface.itweald.com/uploads/files/61356e2023fc4.pdfIn PDF document text
    • http://dailymaydemtien.com/userfiles/files/tonagonufevumaduj.pdfIn PDF document text
    • https://healthtecindia.com/userfiles/file/1193482237.pdfIn PDF document text
    • https://szallas-karpatalja.net/upload/razutubutofidop.pdfIn PDF document text
    • https://nhatngudongkinh.phapluatvietnam.com/upload/ckupload/files/rodolarivuvu.pdfIn PDF document text
    • http://cateringkieuan.com/uploads/userfiles/file/fepujipafimunop.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/woxerafovoworar.pdfIn PDF document text
    • https://surupaceanu.ro/ckfinder/userfiles/files/43603056861.pdfIn PDF document text
    • https://agermag.ro/mm/file/tipiru.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_off0000d0fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0FE 9896 bytes
SHA-256: a7645d5cd5ca2ac97842e5608d312220b8ce65276011cbf6a062eacd902bf05e
font_01_sfnt_off0000e6f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F8 17324 bytes
SHA-256: 7120e31ea7b76ef39f0906b817af7280f108b55c3a7295ae53429c9c42d02c74
font_02_sfnt_off000113e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1