Malicious PDF — malware analysis report

Static analysis result for SHA-256 f38fa968ecb4590f…

MALICIOUS

PDF

78.1 KB Created: 2021-09-17 18:25:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 23bbcfa39186709f619a8254e633245b SHA-1: 310aae14ed1cd3e664184f938be0123403ed3b0b SHA-256: f38fa968ecb4590fb4108e264ef31eced35e6d1efddc80a7c77156a5785ed173
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous external links, many of which are hosted on disposable domains and appear to be part of a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to trick the user into downloading a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://drafthe.ru/uplcv?utm_term=download+pack+roms+mame+android PDF link annotation
    • http://take114.kr/FileData/ckfinder/files/20210907_AD87785F60C7C5B6.pdfIn PDF document text
    • https://sensesgrouphk.com/louis/STARKGROUP/ckfinder/userfiles/files/93272132170.pdfIn PDF document text
    • http://captainkillmite.com/uploads/files/202109140630166935.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/58418486389.pdfIn PDF document text
    • http://zanethompson.com/userfiles/file/29865620359.pdfIn PDF document text
    • http://foodchemsino.com/d/files/73300301067.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/dagirugezonadebuz.pdfIn PDF document text
    • https://tylbm.com/Upload/ckeditor/files/kanedokefanimeme.pdfIn PDF document text
    • http://peak-experience-japan.com/images/blog/file/55017342291.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/loxapezuzorodefe.pdfIn PDF document text
    • https://mashura.co/userfiles/files/wemevojijezot.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/gewimu.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/lufobazaxotenibixilizu.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/totebupeg.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021090417115482.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/34427916810.pdfIn PDF document text
    • https://webmakler.org/userfiles/file/sorurixumimoweriwi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613602f492f64---39488437138.pdfIn PDF document text
    • https://commonwealthsportsawards.com/userfiles/file/sovevul.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/59048271188.pdfIn PDF document text
    • https://biothiennam.com/media/ftp/file/genigivurabugorawoxogu.pdfIn PDF document text
    • https://combrooncom.com/contents/files/vefomujetisufejulorowinim.pdfIn PDF document text
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/b5dd83c383cb0d02454f9d40d84c2e90/diwomexeweg.pdfIn PDF document text
    • http://studiofapas.it/userfiles/files/15843646239.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/saregejotanekufulejopun.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_off0000cfa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFA8 16440 bytes
SHA-256: 73fdc47d839fd0ae0bb32b382a44c2b377936cfcf4c49ac25e012debeb6c1d50
font_01_sfnt_off0000fa23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA23 10756 bytes
SHA-256: 080744962cb6e91b4fd3e55b0503a933d32cbb996e2f20879c177bd085a9c65a
font_02_sfnt_off000112e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1