Malicious PDF — malware analysis report

Static analysis result for SHA-256 a083da8e9763cdea…

MALICIOUS

PDF

72.5 KB Created: 2021-09-13 14:53:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7c35365ca2dad953dac70450686ffcbd SHA-1: 585a1567da83c9410df53f73c8e0f61a28b5ffbd SHA-256: a083da8e9763cdea7ed3b107c296abf4a80520299964b14299fb477f6f6fb7d2
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the numerous unknown URLs indicate a link farm designed to host further malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://polipack.ru/content/file/jowub.pdf In PDF document text
    • http://dubilex.com/userfiles/files/37901970284.pdfIn PDF document text
    • http://alfonsoguiggiarchitetto.it/userfiles/files/mejefuf.pdfIn PDF document text
    • http://feach.ie/images/uploads/file/85260699137.pdfIn PDF document text
    • http://tinhdaurosa.com/Images_upload/files/dijukuvusim.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/zuwakaxabipidimowu.pdfIn PDF document text
    • http://goghepcacloai.com/media/ftp/file/71277439664.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109130512048715.pdfIn PDF document text
    • http://abnicum.ru/files/file/89394381973.pdfIn PDF document text
    • http://everbeenmagnet.com/js/upfiles/files/tazivumapevadofomafemubi.pdfIn PDF document text
    • http://xingzhongjing.com/userfiles/file/20210908090239_476520732.pdfIn PDF document text
    • http://abyss.sk/userfiles/file/62460575543.pdfIn PDF document text
    • http://bdsductri.com/upload/files/juwasefafekowavaxu.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/rimafifuzusezevokeg.pdfIn PDF document text
    • http://dream-mebel.com/pic/file/26197545968.pdfIn PDF document text
    • http://cwesp.biz/upload/file/4241030810.pdfIn PDF document text
    • http://tumakuruvoice.com/tumkurvoice/ckeditor/ckfinder/userfiles/files/tavimukagaruxizetuned.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0ea0d3e6f---varupekanajok.pdfIn PDF document text
    • http://najlepsietorty.sk/uploads/fck/file/17072563285.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/sabubipe.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/navodejenusonagumaju.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/83401749090.pdfIn PDF document text
    • http://xn--9i1b14l32gg2dsybq3b.com/upload/fckeditor/file/kekot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=mini+militia+death+sprayer+sniper+mod+apkPDF 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_off0000b822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB822 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d034.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD034 16660 bytes
SHA-256: bc9c62c0e24a0868c6d69122d3c8769e8a083b5c0bf82885c0811fb3db97f79b
font_02_sfnt_off0000fb9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9B 10856 bytes
SHA-256: af85457684c8dcd68c8bc47b6cfc52bc125c0eaf2aab9ffee81b9631bf53ba92